I went to CMU for phd. They were good when I started there 10 years ago, and they are better now. I'm not sure I could get in if I applied now.
Last time I checked they don't require the GRE, but you might want to take it anyway. The GRE can be a way for you to prove yourself objectively. The test isn't a perfect measure of your aptitude but it can sort of prove that you aren't just some 3rd world retard who got good grades because all his professors were also 3rd world retards because who the fuck knows what the standards are wherever you come from.
I guess there's no GRE subject test in compsci anymore. If you're going into theoretical CS then maybe take the math subject GRE.
