Seriously, Joel, Facebook just needs to "optimize" a bit and they'll be more profitable? Really? With a valuation of $33 billion, Facebook needs to make a bit more than a dime or two extra from their users. They need a ton of real dollars from each and every user or (more likely) dozens or hundreds of dollars from some users and nothing from the rest. How are they going to do that, exactly?
How will Facebook change its platform to convert its hundreds of millions of users, who signed up for a free party, into billions of dollars per year without spoiling the party? No one likes getting invited to a party with their friends only to find that the beer isn't free after 11:30, or worse, they've been tricked into attending an MLM meeting. If Facebook could convert eyeballs to dollars the way Google can, there was no reason not to do so when they had 50 million users, or 100 million, or 200 million... It hasn't been done, though, because it would spoil the party and stop that lovely flow of VC money.
I am just gobsmacked that, within just a few years of the US housing market bubble popping and the financial empires getting caught with their pants down, you would continue to support the speculators' fantasy of pre-IPO tech valuations. These types of valuations aren't just irresponsible or insane, they're scams! The consumers have no money or credit left, so the easy money is going to come from gullible investors.