So,why do you think google is going up and why not facebook/twitter/microsoft?
I like Larry's "google more than Zukerburg's "facebook" because google keeps on developing and it is never done. They built search engine, youtube, webmaster tools, translator, android, maps, still they are developing and yes it is never done.
But,what does facebook do?yey,they have the only "social network" but what's next??What are the progress in developing they made in these 2-3years? I haven't seen any new things and still they are working....
And now the time is moving too fast. Google sees "IPhone" going progressive so it built "Android", it sees "win 8" coming so it is developing "chrome OS", it knows browser has power and it will somehow determine what/how you wanna see web seeing "mozilla" so it built "chrome".
So, google is far more ahead and creative and nothing gonna catch it, not facebook nor microsoft.