Being a reformed CS major myself I checked UCB's CompSci to see what courses they teach and maybe what languages they use... That may be the best indicator of how much horsepower you will need. For undergrad the i5 should be fine, just writing code on a 13" screen is like watching a ball game on a 3 inch screen...
More memory would also be a good idea. 4gb min, 8gb ideal.
You've probably seen this (CS 10: Beauty and Joy of programming :-)):
http://www.eecs.berkeley.edu/Schedul.../schedule.html