I'm playing wait and see at this point. I'm very geeked, but I wan't to know more about gameplay.
Warhammer Diskwars is my current game of choice, but I have Invasion, and LotR LCG. I picked up CoC a long time ago, but have never found anyone to play with so that fizzled for me, though I personally love everything about it. It just doesn't seem to see the table enough.
Anyway, I love the 40k universe, I really want this to be good, but most likely I'll wait to see some reviews before I try it.