Original: In 2008 O'Reilly decided to avoid mentioning Olbermann's name on the air, and once cut off a caller who mentioned Olbermann. O'Reilly has also led campaigns against MSNBC's political coverage without ever specifically mentioning Olbermann.
Simplified: Some compare him to O'Reilly, except that Olbermann is to the left and O'Reilly is to the right.