Keith Olbermann’s final “good night, and good luck” on Friday makes for an interesting media interest story.

Olbermann was a key voice of the left during the 2006 and 2008 election cycles, so he surely could have been fired for being “too liberal.”  With the Comcast/NBC merger complete, several corners of the internet were abuzz with gossip that the new parent company had something to do with the iconoclastic Olbermann being showed the door.  Or, he could just be a jerk who has a history of being fired for not getting along with coworkers.  That’s probably the most likely answer.

For years, Keith Olbermann was the face of the new MSNBC’s left-oriented opinion programming; his aggressive style countered the conservative and populist voices of Fox News with something a bit punchier than CNN’s vanilla lineup.

MSNBC hasn’t shied away from that.  They’re keeping the “Lean Forward” campaign, and their evening lineup still boasts Ed Schultz, Lawrence O’Donnell, and Rachel Maddow.  Maddow will be the lineup’s new cleanup hitter – and for MSNBC, that seems to be the best motivation for the move.

This is unscientific, but do a Google image search for Olbermann and another for Maddow.  Sure, as a liberal lightning rod, there are plenty of pictures of Olbermann designed to make him look dumb.  But as you scroll through, a pattern becomes obvious: few of his pictures, even official ones, include him smiling.  Much like the “special comments” he delivered on his program, Olbermann frequently looks stern, as if the next words out of his mouth might just be the most important in the history of the universe. (See picture above.)

Maddow, on the other hand, is smiling in most of her search results.  When delivering opinions on her show, Maddow is smug and smart-alecky, but clearly enjoys poking fun at her targets.  It’s not necessarily good-natured humor, but it’s humor.  Much like the gruff Bill O’Reilly, one can picture a calmer, non-political side of Maddow, as if she understands that the topics on her show are important, but not likely to mean the end of the world any time soon.

Public relations 101 for anyone who wants to be on TV is to smile… and keep smiling… and smile some more.  It helps the speaker relate to the viewer.  Even when discussing difficult or contentious topics, smiles go further than furrowed brows.  Maddow seems to know this, and thus is a more effective host – and, by extension, messenger of liberal ideas.

That means that the real winners in Olbermann’s dismissal are the far left activists for whom the erstwhile Countdown host was a beacon in the night of the Bush administration.  While he created a place for overt leftist thought on cable news outside the guise of objectivity, Maddow is now the better caretaker of that tradition.

Whatever the real motivations were, the result of the decision is that Maddow, and not Olbermann, is the signature voice of MSNBC as they move (or lean) forward.  That’s pretty good news for MSNBC, but it’s even better news for left-leaning activists.