Yep - I use the WMC Netflixs plugin all the time to watch stuff and it works really well. Fully works with the WMC remote control (my media center is connected to my TV) and it's just like watching TV.
In fact, I've recently finally got rid of Cable TV because I wasn't watching enough of it.
All we need now is an official HULU plugin for WMC from Microsoft..... please....? I know there's third party ones, but they have their downsides.