Cyber Evolution: A counter-strike, day of defeat and call of duty league widely considered to be the first online gaming league in North America to be better than CAL (Cyberathlete Amateur League) This is because of CEVO's highly acclaimed CMN (CEVO Match Network) and CEVO's superior anti cheat software.
CEVO's anti cheat software, while highly popular, has come under fire due to the fact that it scans your active processes (which makes people afraid that their privacy is in danger)
Another complaint is that CEVO has a registration fee while CAL is free. However, most people agree that it is a small price to pay for a league without cheating, with knowlegeble and friendly admins, and for a chance at some prize money.
CEVO > CAL
--the opinion of the majority of the CS community.