I'm not talking about math majors, I'm talking about the selection process for CS students that (from the materials I've seen) heavily favors students who are strong in math and programming competitions specifically. When I looked at the application and the students from my area who were accepted, I realized that I wasn't the type of person they'd likely admit; I didn't have the math and programming competitions everyone else did and my two years of applied CS at my job wouldn't matter much if at all. I was frustrated that CMU only seemed to be interested in certain qualifications that I didn't have. I guess the reason behind "my rant" is that I didn't like feeling unwelcomed by the top university in a subject that interests me because I hadn't taken precisely the extracurricular activities they were looking for.

Meanwhile, other universities with low admissions rates and good CS programs, such as MIT and Stanford, make a conscious effort to consider all facets of an applicant. I wouldn't get in to any of those either, but I wouldn't feel immediately rejected. I mentioned this before, but I think it's a shame that the top ranked university sets itself out this way.

On the college point, the one thing the admissions rep made most clear was that CMU students apply for a college within CMU and that this college cannot be changed once a student attends the university. CS counts as a school at CMU, and so anyone who wishes to switch out of CS (in general) needs to transfer to a different university or just stick it out. Approximately 1/3 of students change majors within 3 years, and even though there's a good chance the number isn't as high at CMU locking students in to CS majors when they apply means that some number of students wanting to switch out won't be able to.