I use a Samsung HL-S466W.. it's a 46" DLP HDTV. The DLP's are dropping in price fast right now. I did alot of research before I bought it, and had narrowed it down to this year's Samsungs and the Sony 3LCD's. They look great.. VGA, 2 HDMI, optical and coaxial out, plenty of options. I have it on a Pioneer home theatre (not HTiB), but may go with an Onkyo home theatre system soon due to the great # of inputs on their HTiB receivers.
Take a look at the new rear projection units, you could find a 42" online in the $1100-$1300 range or jump on one of those "no interest for 18 months" offers that CC and BB frequently offer. The 360 looks great on it.. and I've hooked my PC up to it a couple times and tried a couple games on it. The only downer is not having component cables for my Gamecube.. using standard inputs on a screen that size isn't the prettiest thing in the world.