There are new weapons, new effects, more aliens and it is all comfortably playable on the Xbox.
It's taken me a couple of hours including waiting time to capture the video and edit it using the following tools:
Microsoft Expression Encoder 4 to capture 10 minutes of video.
Windows Live Movie Maker to edit the video down to about 3 minutes, add the transitions and the background music.
Thanks to Purple Planet for the music included in the video.