While I'm in total agreement that Netflix on the PS3 is superior, I base it solely on the fact that my movies load faster and don't interrupt on the PS3. For some reason, Netflix on my two 360's (The Slim uses a wired connection and my 60GB Jasper uses a Wireless Adapater) is a lot less stable--it takes a minute to load a movie sometimes and it often stops in the middle of the movie to say that my internet connection has slowed or stops entirley ("Unable to resume video playback"). Again, this never happens on my other Netflix enabled devices and if the 360 didn't have these issues, it would be my Netflix player of choice.
What makes the PS3 superior is: You can set the system to turn off after two hours--the 360 only shuts off after six hours of non-use--just in case you fall asleep during a late night movie session. It loads faster (for me). I assume it has better audio. That's it.
See, what those links don't show you is that PS3 got the latest user interface a few weeks before the 360 (and Wii). That's why they're all boasting PS3 superiority. The 360 didn't have some of those features, yet. Well 360, PS3, and if memory serves, the Wii all have the same user interface, now. In fact, I can stop watching a movie on my 360 and resume exactly where I left off on my PS3. I do it quite often. There's no great big quality jump from Netflix PS3 over Netflix 360.
360 does offer Kinect support, allows you to watch movies with a friend over Xbox Live, and allows you to spy on your friend and see what they're watching but I don't think any of those features greatly improve the experience. I think having to have XBL Gold to watch Netflix pretty much kills any advantage these features may have caused, anyway. So, take it from a PSWii60PC Netflix user (My PC is actually hooked up to the same TV as the consoles). They're pretty much identical.