The gist of my argument is that Google is a ruthless competitor that enters existing markets, upends them, and isolates itself with a seemingly unquenchable desire to dominate every single market in consumer online services; yet, hypocritically, its leadership describes Google as just wanting to get along, that Google is institutionally a nice company, and that they succeed by “building great things that don’t exist”, whereas what they actually do is build free versions of things that already exist and make money selling ads.John Gruber
That's how I see it. Google's "Don't Be Evil" slogan has become meaningless. I think the company started acting this way when it felt it's core market threatened. Mobile -- not just the iPhone -- was a threat to search and so they had to launch Android lest they be rendered irrelevant. Facebook users were voluntarily providing more relevant data for advertisers than search and Gmail so Google+ was created.
Tying together all the Google properties is an attempt to keep inside a different form of "walled garden". Now Google can track you more easily. They own almost all the major ad networks. They have most of the search traffic. I think they have most of the email accounts in active use. YouTube tracks your viewing habits -- even if you are viewing that video on another site ( presumably with Google ads ). And finally Google+ gets you chatting with people sharing links from web sites that most like have Google Analytics tracking code.