Ian Dixon recently posted an item on his blog introducing a new Windows Media Center tips forum where people can share tips and tricks about configuring and using Windows Media Center. You can find the Windows Media Center Tips forum at http://thedigitallifestyle.com/cs/forums/34/ShowForum.aspx, and it is already populated with a few useful items.
I also stumbled across another potentially useful item on the Media Center Show Community forum that I don't see listed in the Tips forum (yet). As most people are aware, Windows XP Media Center Edition 2005 did not support domain join functionality, but in Windows Vista Ultimate, that functionality is available along with Windows Media Center functionality.
A user posted a list of steps that can be used to share recorded TV content with other computers that are connected to a domain. You can find this post at http://iandixon.co.uk/cs/blogs/mike/archive/2007/01/30/how-to-share-recorded-tv-with-other-media-centers-domain-version.aspx.