Apple: how do they continue to stay as profitable as they are?
Amazon: are they really almost worth as much as walmart?
Google: How much bigger can they get? Ads sales will slow in down economy, they are already slowing.
FB, twitter, don't see alot of upside left. I think the problem with the public market is alot of these companies have already milked their strategy.
Are we in a bubble now probably not but I don't know how much higher it goes either.