I've been watching Southland on the NBC website, and the swearing's bleeped out there, too. My working assumption is that bleeping out the swearing has to do with the format of the show -- like, very little music, sort of a jerky camera, "documentary" style -- like it's a tv documentary instead of a straight-up cop drama tv show.

Granted, I could just be pulling this out of thin air, but that's my idea.