While Alien Arena 2009 brought numerous improvements to this open-source game, John Diamond has been hard at work on Alien Arena 2010. We received a message from John saying this inaugural 2010 release will feature "a host of updates, new content and bugfixes." He also said the release will arrive in a matter of weeks. Though in anticipation of the Alien Arena 2010 release he has put out a trailer (embedded below) and also updated screenshots on this media page.
Alien Arena describes itself as "a fast, fun and free FPS" that has been around since 2004 and is a game we have talked about in years past. It competes with the likes of Sauerbraten, XreaL, and Nexuiz. The last official update to this game was in late December of last year.