I was specifically looking at undergrad rankings. The acceptance rate is not a good filter because that's the acceptance rate for the entire school, not the CS program.
From what I can tell, anyone who is a Harvard student can declare the CS major if they pass the pre-reqs. At Berkeley, passing the pre-reqs doesn't get you into the major -- you still have to apply for a limited number of spots, which generally means having a 3.8 GPA or better in your pre-reqs. So effectively both programs have the same acceptance rate.