I have had the WD Media Streamer for a day now and so far I don't really like it compared to ATV2.
1. I had to setup the wifi settings twice after I powered off and on the device, it never remembered the settings. I have powered it off and on a few times since then and the settings stayed, so hopefully I won't experience this issue again.
2. Slow to start up (compared to ATV2)
3. When I tried to start Netflix, the WD box rebooted itself and Netflix never loaded. I updated to the newest firmware and was able to start Netflix, but on the first time I started it, the box locked up. I had to unplug it. On the 2nd time I was able to setup Netflix
4. The ATV2 interface is much better than WD Live', IMO anyways
5. When I try to watch a video from my NAS, WD takes longer to play the video than watching the same video on my ATV2. Both hooked up through wifi.
Granted I only had a day to play with it, so maybe I will like it as I use it more often. Since this is for my kids, I do like the fact I can control what video folder, on my NAS, that they can watch movies from. So I can just create a kids video folder and only let them access that one. I also read, haven't tried it yet, that I can setup a password on the items in the services section. So that my kids will have to get an adult to enable those services. I will leave Netflix open, but if I can, I will shut down the rest of them.