The range is not that great, with Warner TV (which is not TV shows, but movies optimised for streaming) apearing to be the only range available. However, when 2010 is offered (which is one of my favourite movies of all time), I knew my first choice was already made. I also looked at the second Harry Potter movie for comparison.
I found the video quality to be good, but not great. Things like jittering (like someone holding a camera by hand) and lag during panning shots. I noticed very little artifacts in the stream, and the buffering to be quite good.
The default aspect ratio is not 16:9, with Letter boxing on the sides, however the controls allow full screen, which does take up my full screen (which may vary depending on your own screen aspect).
The on screen controls are what you expect, and should work fine on a TV if set up with a media centre PC or Mac.
If Quickflix goes the way of Netflix, there should be an explosion of devices you can watch the content on. At the moment it is PC, Mac OS X, Sony Bravia TV and PS3 only. iOS and Android Devices may be supported in the future, but not currently.
This is early days for Quickflix, and the range of streaming titles should increase when the agreements are made with content providers. I do believe there is a basis for a great service, but for the time being only early adopters should use this service until the range and device support improves.
Source: iTech Report