Tried this out last night and....yeah, it BLOWS. Even less of a selection than Netflix and you still have to pay for most movies. What's the point of offering it to Prime members if they still have to pay extra to watch movies? I can rent movies from Dish. I love my prime membership and I love Amazon, but this service blows chunks. Basically a glorified pay-per-view service.
Why do companies think anyone will pay 4-5 bucks for a night's rental of a new release when most people can pick up a copy of it from Redbox on their way home from work for a little over a buck.
I explored it a little and it seems OK to me. just make sure to browse under the Prime tab on the top and you have plenty of stuff to watch. It seemed like more TV shows than netflix has but ymmv.
I watched a couple episodes of cheers. I just browsed the tv shows and thought the selection was ok. I'm only paying for the free shipping so anything they plan to thow up there I consider a bonus. I wouldn't expect it to be as good as Netflix.