MSNBC has a story on machinima that touches on Red vs Blue. They also mention Lenny and Larry Lumberjack, who apparently have a new film out. Always wondered what had happened to them.

The article also mentions that Half-Life 2 is supposed to have "special tools" specially designed for making machinima.

Personally, while the Halo engine is extremely pretty, and, once you've wormed your way into its guts, pretty extensible, it's not very machinima-friendly. The earliest examples I remember seeing were Quake 1 timedemos, and as a result, were extremely fast downloads compared to rendered QuickTime or Windows Media videos.

Thanks Louis Wu at HBO.