Are you guys crazy? My gf has the 2.26 model and i have the 2.53 we both have 4 gigs ram. My machine starts up in 33 seconds, hers starts up in 42 seconds. Every app i click starts up one bump faster, not sure if its because she has the 160 gb hdd, and i have the 250. But you can definitely notice the difference in speed. Plus, if your going to be using final cut studio, a bigger processor will fit your needs.
Alot of people say that oh, you wouldnt tell the difference between the two, there just numbers. Im letting you know, that I Can tell a difference.
You probably couldnt tell the difference between the 2.23 vs the 2.4 or the 2.4 vs the 2.53 but the 2.23 vs 2.53 you can tell. just my $0.02...