Today Google launched a beta of their latest foray into social networking, social search, and social in general, called Google+. Wired has a great writeup about the design and engineering efforts and the purpose behind Google+, but I think this quote from the New York Times' coverage says it all:
Mr. Gundotra and Mr. Horowitz said that knowing more about individual Google users would improve all Google products, including ads, search, YouTube and maps, because Google will learn what people like and eventually personalize those products.
That's what the game's really all about.