I said before i didn't have faith in valve to pull something like MM off given their track record with tf2 but I got called an idiot and that Valve really was listening to the community this time. I'm still salty.
Valve has no record of supporting any additions they've made to tf2 past a few months (except hats) , and MM is very very quickly reaching that limit. We should expect them to stop working on it after the next couple updates probably and if those don't take off it's completely dead.
Honestly now, it's probably far too late. I was queing on a weekday evening, about 7pm pst, what should be absolute prime time for gaming, less than 700 people qued for MM in the world. Every match I was placed in had most of the same people in it, just scrambled around. That's an embarrassingly low player base. What incentive does Valve have to work on a game mode .01% of their player base actually uses? One that doesn't earn them any real money yet requires a significant investment from the small TF2 team?
Many developers would kill to have a competitive scene with the passion and dedication that TF2 has, and would support them hand and foot, but competitive TF2 has really existed in spite of Valve rather than because of them. It's time to accept MM and Valve are more than likely never going to be the savior of competitive TF2, and that competitive TF2 is nearing the end of its lifespan, there's only so much a community, even one as passionate as TF2s, can do in the face of such disinterest and disregard by the game's company.