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Wikipedia reports Gmail has 193mm users, so even if Google plus integration starts, they're still behind Facebooks 600m+. FB has already made nods towards improving their communication inbox features, it's a feature war.
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But yes Millions more on Google Search... No profiles.. but that has to count as well..
Yes, but more than 60% surfing people use google for search, many will response to the +1 button and register to google+ I guess.
How many searchers does Google have per day? They can start marketing to this group pretty heavily, and include social info in search results.
What a shame Apple could never make a dent in this space, but then again, they are bigger control freaks than FB (I'm a Mac girl but fully recognize the sickness)
On another note, I actually look forward to ads from Google in here if they are anything like Gmail's. They can easily double their revenue once G+ is fully operational and public. Facebook is SO in your face, good thing I use an ad-blocker.
I believe the issue Facebook has here is that Google+ is not simply a Facebook alternative. Google+ brings so much more to the table and further integration with other Google services will only highlight that even more. It is these outside cases that Facebook don't really have a vision for that will make Google+ such an amazing community.
Facebook is making one error after another.

1. Made fonts small. Harder to read.
2. Wouldn't let me upgrade my Group to the NEW Groups.
3. Removed the POST/SAVE key on comments. Who does that?
4. Limited the # of followers I can have and has no personal page, fan page conversion.

I like it here.
Come on +Jeremiah Owyang , there is enough place for 3 or 4 big social networks out there; I know perfectly that social media web evangelists get incredible attention to comment brand wars. But believe me, this trend begins to look pathetic.
I think beyond just features, it's going to be how google will use existing g+ users to rope in their friends to be more active on g+ instead. People go where the majority of their friends are. For one, i like how you can message a circle and have those without g+ accounts receive an email instead. I just wish the invitation system wasnt throttled. It would have been a really quick way of winning people really quickly...
As long as G+ does not participate in a Federated Social Web it is just another (well-done) silo.
Can't wait for G+ to get out of limited field trail and open the barn doors. I started using it last week and haven't used FB ever since..
yes but Google has 1B search users, and that black bar at the top will be everywhere. 95% of the time I come back into plus it is via that bar through other apps. they are bundling and fighting in the same way Microsoft did with IE against Netscape
+Thierry Lhôte Assuming no open social protocols --> how many sites do you want to maintain friendship relationships with? (inviting, pruning, discovering, adding)
I don't see it as an either/or proposition. G+ will just start to siphon off time-on-site on Facebook, for those that want to do more Interest Graph-y things over here.
I think the bulk of FB users are nothing like the people having debates on other channels about where 'Social Media' is heading....
+Jeremiah Owyang But how many users have a Google account sans a Gmail account? To create a Google Profile you only need a Google account...same goes with YouTube and Blogger. If Google was to prompt every user who signs into YouTube and Blogger to "connect/build/link" their Google Profile then the number game would be different.
Let's also not forget their 500,000 Android activations a month and a lot of social networking happens on mobile devices.
Do you consider it's all question of numbers? How many active accounts? How many young people / professionals? Maybe FB will stay for younger and G+ for more seniors. They are good collaborative work potentials with G+
I agree. I don't think there's much here that FB can't duplicate. It's a fun race to watch. 
Tara lots of young ones are not engaging with Facebook. It's a closed system and in the end open ones tend to overtake closed ones once enough of the audience is comfortable with them. Facebook is the AOL of the 90s.
I think this is why they're looking to integrate more of their products. Gmail alone may not rival Fb, but when you combine Gmail, YouTube, Picasa, Blogger, etc. under one umbrella you get a powerful user base.

I know plenty of people that use Blogger and YouTube, but don't use Gmail as their main email account. If Google requires all of their properties to create a g+ profile it could help adoption, and it'd be death by a thousand paper cuts for Fb.
+Harry Hawk [added you to my circles] there is no need for an open social protocol, Apache Wave (which is an Open Source project now) can provide that. And the backing protocol XMPP still exists too. So there is need for an open social network, distributed, yes, and it will happen. Now, I believe that Google will have the technological possibility to connect further to these. A ancient Walled Garden like Facebook, will always have DNA difficulties to adapt. Until this day, I cannot see problems in having in limited numbers these social networks.The debate about open an distributed social networks is old now... was a salient point at the time of the death kiss of Facebook on Friendfeed, though...When Scoble welcomed it and propagated it as Great News... On a10 years scale, your preoccupation is just thermal noise... open and distributed social network will come, and Google will be more ready than others, thanx to their philosophy.
How about the # of Youtube users?
+Tom Masiero your right, YouTube users have Google Accounts.. I guess the real question isn't how many youTube or Gmail accounts but the total # of Google Accounts..
I find it hard to believe that Gmail only has 193m users given that almost everyone I know has a google account (even accepting this isn't necessarily a representative sample)
Google has a huge opportunity when you layer in G+ across a future version of Android that Facebook can't do.
+Steve Banfield Sorry Steve, the purpose and credibility in Android for Google was to bring the Web open standarts to the mobile. Not to lock up a platform "à la" Apple.And like +Bryan Eisenberg said 500.000 Android activations a day, will bring a lot of opportunities for everyone.
Why are you using Gmail as a barometer when the big news this month was that Google had 1billion monthly users? We can already see where/how Google is going to embed G+ in more than Gmail. Facebook was losing average users in the US before G+.
Yes +Rob Rollinger and let us not forget that little +1 which is going to have meaningful impact on SEO and Search results which will force more businesses into social presence
+Thierry Lhôte +Rob Rollinger G+ is already a good App on Android and I think as a rabid Android fanboy I would love far tighter integration. If G+ can back propagate locations and messages then I would use G+ much like HootSuite and push messages out to G+ via Circles when I need privacy to hit particular communities and then push to Tw and FB, etc. as I desire
+Thierry Lhôte I agree 100%. I was talking about the SEO impact of the +1 button before I even got a glimpse of Google+. Google doesn't often give SEO pros a way to increase their rankings. I predict +1 will get mass adoption on web sites for this reason and will be Google+'s secret weapon.
FB has really strict TOS for contests and sweepstakes and it would be really interesting to compare with G+ if G+ is more flexible.
yes +Rob Rollinger Google for the next few months are connecting the dots between their "Internet presence" Search - Applications - Mobile. This is some sort of New Media definition. Knowledge flows over Knowledge Stocks like John Hagel's big shift
+Thierry Lhôte Whatever the purpose of Android was, Google will take every opportunity to leverage that platform with G+ against FB, Twitter etc. Deep integration of Google services under a unified brand is a powerful weapon. There will be multiple social networks of course, but Google has to control its own data and user interest/activity data to retain its position in search.
Someone over on another thread pointed out another likely source of users for G+: YouTube users... they all have a Google account in a way! YouTube is in need some UI clean-up anyway... and it won't hurt to offer them G+...
I think the winner is going to be the one that makes its platform more open and easy to integrate with the rival. If Facebook keeps getting all private and don't want to share anything with G+ then it will be more likely that people prefer to stay at G+ because it already integrates some things with FB.
It'll be a battle of 'trust'. Features don't matter if we don't trust the platform with our info.
+Gabe Diaz Great point about Google Accounts not requiring a Gmail login - this was one of the flaws of Buzz, it was way too coupled to Gmail. Which relates to +Bryan Eisenberg 's comment on the 500K Android activations a month - small in comparison to overall Google Accounts, and no doubt overlapping, but clearly Google has the advantage of hundreds of millions of devices out in the field that can be G+ enabled by default. Google is now the only major mobile phone vendor with its own major social network and the leader in total smart phones by a comfortable margin, according to recent comScore data. That's something to think about.
Yat Siu
Don't know too many companies out there that have won on "features" alone, or for that matter, quantity of features.
I'd say the bigger difference is in culture. Google doesn't start a project to make money...though I am sure they will find a way. Facebook on the other hand...well, remember the scene from "The Social Network".."you know what's cool..a billion dollars." And Facebook is clearly there.
I agree FB will struggle more and more. But they have a chance -- see "Why Google+ is the best thing to happen to Facebook" in Ad Age
+Jeremiah Owyang +Judy Shapiro +Tara Coomans Hereafter is what I really think:

... Only constant creative feature development will determine how Google will change Social Media globally. The way they will be dealing with spamming apps and the way they will be offering enhanced non-invasive privacy options will determine true user loyalty. Should they stop now, they will be nothing but excellent fat-green-noted copycats. Google+ could in fact be a better place for interaction and online commerce with only 100M subscribers than Facebook with its 3/4bn user-base...
But is it really a "war"? If FB has such a dominant control over user populations, isn't really more about a more compelling feature experience than a "war"?
+Jeremiah Owyang's analysis seems to be off - it's comparing apples and oranges. There are an estimated 6-700 million people with Facebook accounts, but only about 160 million total unique visitors each month to Facebook, according to comScore . On the other hand, research by eMarketer indicates that most people check their email several times a day. Assuming for the moment that only about 2/3 of Gmail users make use of their Gmail account, that would still make Gmail users reasonably equivalent to Facebook users from the perspective of total unique visitors.

That said, I don't think that Gmail is a very accurate barometer for measuring Google's user base. Many people use Google Accounts and Google products actively who do not use Gmail. Many of the email invites that I have sent out have not gone to Gmail accounts. So I would assume that it's safe to assume that Google will draw on an enormous base of people who use their platform daily, with or without an account login.
I think G+ can get 20-40% of FB users, not to abandon FB, but to spend serious time-on-site here. So anything from 150M - 300M eventual G+ users is a total win.
What we need here is some "friendly" competition then the end user wins.
+Alex Schleber ...Im with you mate ;)

Ultimately, it comes down to what users do online (what actions they take ie. purchases, time onsite etc). If they're helping to make Google, Facebook, Twitter money, the number of users stats are a peripheral gauge.

Window shoppers never keep anyone in business ;)
+Mahei Foliaki time-om-site is everything. G+ will win the Interest Graph, because FB can't really fully go there by nature of its set-up. Sure, people hit "like" on their interests, they may even comment. But do they strike up conversations with strangers about them?
right on +Alex Schleber ...simply look at this thread alone. approx. 60 comments. I wonder if +Jeremiah Owyang receives this feedback via the other channels (incl blog).

Google+'s open setup with PUBLIC and EXTENDED CIRCLES is akin to Twitter in the early days which is a beautiful thing. Serendipitous conversations and connections from anywhere and everywhere. Connecting via interest is fuel to this fire don't you think?
I believe people tend to share more when talking amongst connections with similar interests, because they know that these folks give a damn about what they are talking about, same goes for everyone else in the group.
The important question is, how many unique people use google? That rate the web thing is a better sales pitch than anything.
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