>Just to pick a nit. To date Facebook's P/E is high because Facebook said so. Facebook's value has never been set by an open market until about 3 or 4 hours ago.
Not an open market, no, but a market nonetheless. Anytime a company takes a funding round, whether from a single incubator or a dozen VCs, the transaction implicitly prices the company pursuant to growth expectations. (And that's not even mentioning Facebook's heavy trading in SecondMarket.) Just because a market is restricted and low-volume doesn't mean it doesn't exist; any time a transaction occurs, you'll find a market behind it.
Not an open market, no, but a market nonetheless. Anytime a company takes a funding round, whether from a single incubator or a dozen VCs, the transaction implicitly prices the company pursuant to growth expectations. (And that's not even mentioning Facebook's heavy trading in SecondMarket.) Just because a market is restricted and low-volume doesn't mean it doesn't exist; any time a transaction occurs, you'll find a market behind it.