Theyare most definitely not DOA. Media Center PC's will be exceedingly expensive for the first year though. Sony sells the only HDCP compliant media center pc right now. Sonystyle.com
What the pc enthuasists should be pissed off about is how the current top of the line Nvidia and ATI cards are not HDCP compliant even though many have been advertised as HDCP ready.
just a note, you already can build a hdtv PVR on xp.
you don't need vista and xp will be my last microsoft OS.