id software announced that Wolfenstein: Enemy Territories source code is being released under GPL. There's no official press release/announcement available yet but you can find out more details on the Splash Damage website.
"During his annual QuakeCon keynote speech last night, John Carmack mentioned that the full Wolfenstein: Enemy Territory source code is now available under the GNU General Public License."
Source can be downloaded from the following locations: id Software FTP, Rapidshare and Splash Damage
[UPDATE] According to a number of sources[alt][alt], id software have also released the actual source code for Return to Castle Wolfenstein, similarly under GPL, which can be downloaded here for Single Player source, and here for Multi-Player source.
"And that’s the next point. As some people expected … the original XreaL game project is dead and I won’t waste my resources on dealing with artists again."Was there some bad mojo hanging around with the original XReal project or something?