Well, I have had a 12" Powerbook G4 (1GHZ, 1.25 GB) for the past 2 1/2 years and absolutely love the size. It has never given me any problems. However, I am working on a very big video project right now (lots of short 5 second clips, slo-mo, effects) and I keep dropping frames upon playback. I have tried all of the suggestions by people on Mac boards, DV editing boards, and the Apple Store and while some of the changes I have made have helped a little, I still can't watch the project all the way through. It will be impossible to have confidence in the final movie (or to dump it to tape) without the ability to do this. Most now think I need to get a faster computer. I, of course like the Pro (for the video card and sturdy case), but I don't know about the 15.4" body. I travel a lot and the 12" is perfect for airplane tray tables. And I'm not sure that the regular MacBook will be so much better than my current set-up that it's worth a $1500 investment...