I've been thinking about maybe attending that show but will probably be in Ocean City that night.
Saw Múm play the Black Cat about 2 years ago. Kurosawa and I met up and very much enjoyed the show. Actually, we both went to see the opening band, Phaser, but wanted to see Múm too. They did surprisingly well there as they are very quiet which doesn't seem to bode well for the Black Cat.
I have the new album and it's pretty good but must be listened to in those reflective and peaceful states of mind.
If you are thinking of going, I would highly suggest that you go. But don't hang out in the back...unless you are one of those very annoying talkers. In fact, if you are, don't even bother to go to the show.