I agree, it's most likely it won't be any close to Google's if that's what people is thinking.

In fact, social content is hard to monetize due to privacy concerns, thus IMHO Facebook is lacking of a clear long-term business model other than advertising. Google's investment in Zynga doesn't help that much either.

They have taken the right path targeting developers but I don't seem to understand where that is going.

So my answer is no, I wouldn't buy Facebook stock, except for speculation purposes.