A new CVS compile (by T3CH) of XboxMediaCenter has been released.
This T3CH-compile is a BAREBONE package (so less stuff that can cause issues) compiled with XDK v5849.
Here's the added and updated stuff since the 2005-08-16 CVS release - for the full changelog including the fixed and changed stuff go to the forum thread:

* updated: mplayer.dll (fixes ogg in mkv's and ogm's)
* added: exception handling to threaded renderer (includes changes to how graphiccontext was locked to allow it to be unlocked properly on an exception)
* added: visualisation.enabled tag to be used in skin conditional visible tags, enabled means a visualisation has been set in settings.
* added: zip/rar support in webserver.
* added: file manager, calculate folder size for multiple selected items
* added: Short crossfade on manual trackchange/skip if crossfading is enabled.
* added: Option to en-/disable albumtrack crossfading if crossfading is enabled. (files must be properly tagged with albumtitle and tracknrs and must be scanned or id3 option enabled)
* added: setting to enable/disable how items starting with "The" are sorted in Music and Video
* added: ability to jump into the library view at specific locations using "genres", "artists", "albums", "songs", "top100songs", "top100albums", or "recentalbums" in xbmc.activatewindow() as the destination parameter. ex: xbmc.activatewindow(mymusiclibrary,top100albums)
* added: option to hide file names in thumbs view in My Pictures
* added: System Info: System Uptime [GeminiServer]. Will display the Time that have elapsed since the system was started! It will display Minutes, Hours and Days! The display values will be Autodetected!
* added: if a incomplete rarset is detected, we hand mplayer the '-noidx' switch.
* added: progressbar to rar caching.
* added: Recent Albums to Music Library, presents a list of the last 25 albums scanned into the database.

You can add more scripts and skins yourself if desired. You can download them from allxboxskins.com, xbox-skins.net and xbmcscripts.com.
Keep in mind this is a CVS snapshot of the current development tree. It's not a official (stable) point release. Use only if you know what you are doing.