Potentially, but the problem becomes that none of these companies will ever make money - you can't stay on the VC treadmill forever, and over time it's going to be harder and harder to monetize 'SELECT COUNT(*) FROM USERS'

The other problem is that you can't pick the winner in every horse race. Facebook obviously won this round, but it just as easily could have been Orkut or any other social network that was out there. The traction model is almost certainly chaotic.