Today HP announced support for YouTube on its HP MediaSmart connected entertainment products.

The soon to be released MediaSmart Connect digital media receiver and the high-definition MediaSmart TV will be bringing Youtube videos to your living room.
HP worked with YouTube to make it possible for people to watch and share full-screen videos on their HDTVs and to create multiple playlists from anywhere they watch TV: You simply log into your YouTube account with an easy-to-use remote control and start watching videos on their HP MediaSmart products. With Youtube support once the MediaSmart Connect digital media receiver is on the market HP will be competing with the Apple TV.
HP already sells the MediaSmart HDTV HP SL4278N with integrated media streamer that sells for $1,899.99.
Via the HP site.