I didn't realize that the RtCW and Enemy Territory engines were really that different from one another... or that different from the Quake3 engine for that matter. Shows what I know.

I can't wait to see the Doom3 engine opened up. I can see that being very appealing to hobbyists. Of course, we may be waiting awhile, since there are still commercial games in development using it. Actually, I thought Wolfenstein (2009) was one of the most atmospheric games I had ever played. The mouselook was just slow and suffered from console-itis.

Ummmm, I'm pretty sure they've been available for a long time (unless I'm insane -- which I am, but I mean the driveling idiot insane).  I remember after I played through the game, I edited the code to add guns, modify them and destroy nazis.  However, maybe that was just game sdks and not full engine code -- I don't remember the full details.