While I haven't ordered it yet, I got to play this at Arkham Nights, and we had a really fun time. While not as creppy as some of the other scenarios, the theme was great and I loved how the story played out. And, like most MM games I've played, the players literally won on the turn where has they not compelted the objective the Keeper would have won on his turn.
There's actually a part of me that hopes they can turn the storytelling aspect of MM into mini scenarios for Arkham Horror. I love both games, but sometimes it would be nice to play a slightly more linear game of AH.