If it's cold, dark, whatever outside I can call an Uber via the app and know when they're arriving. I can see how long the expected delay is to plan wrapping things up accordingly.

My experience with Taxi's in most of the major US markets is that coverage is spotty, fares can be variable, credit-card acceptance is hit or miss, and the cars and drivers are generally sub-par.

Comparing taxi's to Uber is like comparing a model rocket to the Space X program.