Handbrake, the popular video transcoder, has been updated for 64-bit support. They claim 10% increase in performance. I’m seeing a little over that on my MacBook Pro (early 2008). I still haven’t tried it on my Mac Pro but I think it will get even better with 12GB of memory and 8 cores. They also trimmed the fat of the application to speed things up. Most are still probably going to see performance in the 22 to 30 fps but that’s close to real time so a 2 hour movie will take 2 hours to transcode. They offer a live preview so you don’t have to do the entire movie to see what it will look like. You can find out more about it here.