That's me sold. I'm in the process of ripping my (60 or so) DVDs on a PowerBook and it's painful encoding h264 - about 6 hours per DVD.
Even if it takes 2 hours or so, I can get 4 done every night rather than the one I currently get. I currently get a max of 2 a day, meaning it will take a month of serious processing to get them done rather than 3-4 days with a MacBook.
(Plans trip to get new mac this weekend - and excuse that wife will accept to get one)