She was once just another Western Massachusetts liberal lesbian appearing on WRNX in Amherst; then she became all national on Air America; then she got big-time as MSNBC's "it girl." Well, now Rachel Maddow apparently is getting her very own prime-time show on that network, replacing the guy who has that show that signals that it's time to turn the dial. (That would be Dan Abrams.)
I think MSNBC has been desperate to put a woman in the host chair for a political show, after Chris Matthews and Keith Olbermann took so much heat from Hillary Clinton supporters for alleged sexism. That kind of exposed the fact that virtually every political talk show on TV is hosted by men (with the exception of Gwen Ifill on PBS, and Campbell Brown's new CNN show). Fox News probably doesn't care about having an all-male line-up, but I've always had the impression that MSNBC needs female eyeballs.