UT2004 Editor's Choice Edition Released
Neophytus writes "Earlier today the 'Editor's Choice Edition' addon for Unreal Tournament 2004 was released to the public. The official bonus pack contains new maps, models and vehicles for UT2004. The ECE torrent is available, alongside direct downloads provided by BeyondUnreal. Rereleased alongside, the Game DVD bundles eleven of the best community-created mods alongside the new content."
The current version of UnrealEd is done with lots of Win32 code, but I believe they are basing the next version (for Unreal Engine 3) on wxWidgets. That should make it pretty easy for them to port it to linux.