Sorry mate, I know how impatient you feel. There's been speak of it not returning. I wish that is not the case, or at least we are allowed to export our maps elsewhere. All us Map Maker dudes have been waiting for the server to get back up, and it's been numerous months. The old word is that it comes out after MW 2.0. We have no confirmed date on that either.
I'm not even sure where 50% of the MM community went. Guess we're gonna have to wait though. Hopefully we get an official answer soon.