Looking for a decent excuse to advance his long-simmering feud with Rupert Murdoch and to do a weird Australian/pirate accent, MSNBC's Keith Olbermann seized upon the words of a former News Corp. insider, who claimed in one of our posts this morning that Murdoch fired Jane Friedman from HarperCollins because she canned powerhouse publisher Judith Regan in late 2006, and also because she squashed Regan's OJ Simpson book project. The source also claimed, tangentially and outlandishly, that Fox News chief Roger Ailes will soon be fired as well for his own role in the Simpson book fiasco. Predictably, this amused Olbermann to no end. For the crime of going to bat for the OJ book, Olbermann named Murdoch today's "worst person in the world," an honor previously bestowed to Fox News screamer Bill O'Reilly. He then did a killer Murdoch imitation that will surely put to rest those allegations that he's totally crazy. Clip after the jump.