There isn't be a bubble until Facebook IPOs. If there were really a bubble, Facebook would have IPOed already.
The longer they wait, the better it might end up for the rest of us. The SEC suffered major embarrassment when Americans were dropped from Goldman's (?) recent Facebook investment vehicle and is at minimum looking to revise the current rules which date back to 1935.
That's not going to fix SarBox, but maybe, just maybe that sort of bad attention/publicity will help.