I just got finished watching this a few minutes ago. I'm quite impressed with it! They're definitely taking Mortal Kombat in a fresh, new direction. In particular, the interaction with the arenas seems to be among the best ever in a fighting game.
The side games all look nifty, too. A board game, puzzle game, and even a role-playing game offer added gameplay beyond what you see in most traditional fighting games. All of them look like they'll be fun to play!