> Never heard of it.
If you've truly never heard of it then you haven't been paying attention. Look at the list of sites that use MT: Boing Boing, Read/writeWeb, TPM, Huffingtonpost, O'Reilly Radar, NPR, New Scientist, Intel, Oracle, Adobe, ... That's not even including all the TypePad blogs like Cute Overload, Wil Wheaton, The Daily Galaxy, etc. or large group blogs like scienceblogs.com (Pharyngula, Respectful Insolence, Scientist Interrupted, etc.)
MT may not have the mindshare of WP but it powers a shitload of sites that you probably use often.
I know exactly why WP won. got to the movable type website (http://www.movabletype.com/) on the right hand side is a small showcase slideshow of websites using it. The first one was Britteny spears and the second was Comcast... I was really worried Nickleback would pop up too..