Its flabbergasting to think how they were valued at $100bn at IPO. I don't use Facebook, but I know that many people in the developed world who are already tiring of it. It may grow in the developing world, but what use would that be in terms of increasing revenue. The only people I know that use FB do so to pass a bit of time and mess around with friends.
Be warned, my friends, FB is another MySpace that will be worthless in a few years time.