I've read a number of statements from Uber, and talked to every driver I've had. My understanding is that they all are required to be licensed (and in fact are already limo drivers who are filling free time). I haven't run into a driver yet who drove for Uber full time.

I've also found that I've gotten uniformly glowing assessments from all my drivers about Uber. This past weekend, my driver told me that "Uber is the best thing to happen to the transportation business ever". He had driven taxis, limos and worked as a delivery driver before. I hear similar stories from all my other drivers. It's certainly a different experience than riding in a taxi, but it's always hard to generalize from my limited number of rides/drivers.