"Microsoft said recently that its Windows XP Media Center software is outselling the standard edition of the software" ... somehow I have my doubts on this. WinXP MCE cannot be bought through retail, it can only be had through a new system. So if an OEM puts out two identical machines with a plain WinXP and one with MCE on it for the same price, guess which one will be picked by the consumer?
On the other hand, if MS were to sell retail versions of MCE, XPT etc, it would be interesting to see how many users would buy them to upgrade their machines.