Decline and fall of the Roman Empire for Google for sure. I think social scared them about as much as a company can be scared sort of like how scared Microsoft was of the web.
Turns out they both were right to be scared (lol). As we move toward semantic web, a web of meaning and context checked by social, what we know as Google will be all but gone.
I just created a Haiku Deck about how web design changes in a semantic web time (http://sco.lt/61eqNF
if you are interested and sorry to pimp your post).
The reason the big G is worried and closing the gates is app-ification + semantic could be a difficult combination for their $. Google's system depends on the VOTE of a link (or link expressed as social share).
What if we LINK LESS? What if we SEARCH LESS? In an app-based world where I watch my Amazon movies without every appearing to go to Amazon (at least as far as Google is concerned) how relevant and true is Google's traffic analysis?
Last night I fired my Amazon app to watch Inspector Morris and Google has NO VIEW into that click or time on site, none. As the mobile web dominates we will app-ify all of our code.
My deck speaks to our adoption of the Google float. Once our websites are What If math then we can be said to be fully app based too since what Google's spider "sees" is nothing.
Nothing because what you see when you go to my website will be different than what someone else sees based on your cookie. That cookie will say what persona you belong within and so what website you see.
If Google has value in the world described in the Future of Web Design it will be VASTLY different than counting links. I think THIS anticipation of OUR future floats is why Google is insisting on having us all logged in all the time.
Once we are logged in we are using Google's app in a similar way as my use of Amazon's last night. We disappear to anyone other than Google allowing Google to create a new value system NOT based on links.
Semantic web is that new value system not based on links. Google will have so many signals and so much big data on behavior they can craft a new voting booth for their SERPs pages - one that may just remain elegant and relevant even in a world of meaning controlled by apps.