The Richmond Times-Dispatch has a small but decent overview of the Microsoft Windows XP Media Center Edition 2005. The most exciting part is the support for Media Center Extenders:


Another significant new feature is support for Media Center Extenders, appliances that allow streaming most of the content on the media center PC to other rooms over wired or wireless networks. Downside: You'll have to shell out an additional $300 per extender. A less-expensive alternative, if you own a Microsoft Xbox connected to a home network, is a $65 CD that turns the gaming system into a media extender.


You can also find plenty of Microsoft Windows XP Media Center Edition 2005 at Microsoft's Media Center site.