Mike Allen of Politico reports anonymous sources are saying Olbermann’s suspension was because he wouldn’t apologize on air. Allen adds:

Olbermann may not hold as many cards as he thinks. He makes $7 million a year and MSNBC’s prime time is not as dependent on him as it was before the addition of Rachel Maddow and Lawrence O’Donnell, who make considerably less.

More to come, I’m sure.