The biggest winners will be those who can cash out quickly. Goldman and some overseas investors.
Long term I think the Facebook _data_ will be sold and resold (licensed) many, many times. It may end up with a company (or companies) that today does not exist. The legacy of Facebook will be the data. We told some antisocial nerd who our friends are. And he sold us out.
Facebook the entity will probably fade away, probably by being acquired. The value is the data. They just managed to get an enormous amount of personal private information for free.
It's an amazing thing to have 800 million people give you their email address, a list of their friends and possibly additional personal info. Certainly there is potential value there. But that itself does not a business make. In my opinion. We'll see what happens.