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Starting today (23 mins go, believe)...

#1 - The first rule of Google Plus is, you do not talk about Google Plus.
#2 - The second rule of Google Plus is, you DO NOT talk about Google Plus.
#3 - If more than two people in your stream have already re-shared a post to what appears to be similar Circles, you don't need to.
#4 - Choose your Circles membership wisely.
#5 - One post at a time.
#6 - No animated gifs.
#7 - Hangouts will go on as long as they have to.
#8 - If this is your first time in Google Plus, you have to post.
John Hoffoss's profile photoLeRoy Lee's profile photoDustin DeKoekkoek's profile photoWill Adair's profile photo
I think a 9th should be in order;

#9 Self aggrandizing and marketing have no place here.

I'm not sure 100% on that though. I like seeing my friends talk about their upcoming shows and what not, but I don't want to see links to people talking great about your business or whatever.
Except you can't tell to whom a user has shared a post...only shows "limited" or "public".
After a point, Circle membership will be decipherable (to a degree)
I'm guessing we'll get the option (opt-in) to share the group names we post to.
I don't think number 3 is the users problem. If you want to share something that is what the network is for and I think Google needs to sort out the problem.
I attempted to improve on your idea.
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