I really like the look of this Pokémon, it seems Gamefreak and the Pokemon Company have raised the bar, and nonetheless, Z looks really cool.
I get the feeling that it's an evolution of Mightyena, which is weird, because they're also handing out bags, with Mightyena on it, and the complete cast of the 13th Movie (excluding Z due to it being unveiled today)
It also comfirms Ho-Oh and Lugia are in as well.
And also the complete cast are surrounding Mightyena, so that could be a hint.
I think that Z will be Dark/Fighting type, since it has a strong muscular build, and because I think its a possibly evolution of Mightyena.
And that the Illusion bit, could be the transformation it goes it into, maybe it will be the first Pokemon to evolve then revert back to the previous stage?
That sounds to much like Digimon.