From the article:
Have you ever wanted to just sit on your couch and watch YouTube on your TV? Well, now that's possible via YouTube for Television, initially available through the Sony PS3 and Nintendo Wii game consoles at www.youtube.com/tv. Currently in beta, the TV Website offers a dynamic, lean-back, 10-foot television viewing experience.
No YouTube for Xbox, however (Google must simply not have gotten around to Microsoft yet).