HDMI and compent is mostly nothing more than the placebo effect when dealing when anything less than 1080i. The colors are a LITTLE different...and it doesnt matter if you plump down $100 for a monster cable by by no means on your average hdtv does it make more than a few % difference. Some TVs I swear were purposely made so that hdmi would look better and that component would look inferior....its a scam.
Assuming this is real, it probably won't be available until Holiday 07. It supposedly has the CPU w/ smaller die and MS delayed the transition until mid-07 already.