Heresy Mansion House
I'm slightly less than optimistic about how well this is going to be handled.
Um...yeah, that doesn't look like it is too interesting, but then, I play Armored Core, so who am I to talk ^_^
But yeah... the most interesting aspect would probably be the usage of demons, but I couldn't make heads or tails of the interface in the gameplay footage. Plus, it is basically just pets, only I think you might be able to do more with them. I don't really know, I only played one MMO for a short while.
EDIT: I take that back, I understand it, I just don't know what anything means on the bottom bar.