I would not be surprised. When you are a multi billion dollar company anything is possible. Where did you hear about this?
Most likely google simply wants a piece of the cake seing what great potential Facebook has and what big money dwells in social network along with the possibilities for marketing it creates. Also, with google it may actually happen that they'll take over on the long run, pretty solid company.
Google studies the market thoroughly before taking the plunge in to any new initiative. Another new project in pipeline at Google???
Well google has already created their social network before and failed . If they try again and call it google social network and make the platform simple and easy like how Facebook was before than they'll do well.