As mentioned by Crito, the taxi medallion system exists here, and it's a terribly broken system for everyone involved except, perhaps, the Taxi companies. A NYC taxi medallion can cost millions of dollars.
That said... the Uber black car drivers are licensed, only as private limo drivers rather than taxi drivers. They're not allowed to accept street hails. (Before smartphones, this meant having an advance reservation in place.) They're perfectly qualified to drive passengers.
And unlike most regular taxis I've experienced in the SF bay, Uber drivers aren't on their cell phone during the entire drive, so they're arguably safer drivers.
That said... the Uber black car drivers are licensed, only as private limo drivers rather than taxi drivers. They're not allowed to accept street hails. (Before smartphones, this meant having an advance reservation in place.) They're perfectly qualified to drive passengers.
And unlike most regular taxis I've experienced in the SF bay, Uber drivers aren't on their cell phone during the entire drive, so they're arguably safer drivers.