We've got a 2.0 Ghz Macbook (integrated GMA950 graphics) and an external hard drive we've been using to import, edit, and save iMovies, using a DV camcorder. The process is slow but bare-able. I'm wondering how much of a difference we'd see if we bought a 20in iMac 2.66 Ghz. What aspects of the hardware influence using iMovie? CPU matters I'm sure. But what about graphics chip, frontside bus, etc? Would we really see a big difference in terms of editing/saving going from the Macbook to the iMac? Thanks!