Thought I'd answer here instead of the BF post about the capture I use.
Actually it's one that just came out in June. It's called the Elgato Game Capture HD. It works for both PS3 and Xbox (and TV really). It's one of the only ones that lets you capture with an HDMI cord.
It's really this simple to use.:
http://www.youtube.com/watch?v=mgLBNN67KZs
I got mine from Amazon this past weekend:
http://www.amazon.com/Elgato-Capture...ame+capture+hd
I'm not the best at using it yet, but if you have any questions let me know. I'll try to answer them for you.