I'm pretty sure it will be crap.
First, it will all be about DLC bullshit warhammer is perfect for this.
Second, the fun part of warhammer (especially the new gen) is the randomness. Especially the randomness of magic. I don't think they will dare to put as much of randomness in their game and I'm not even sure it would fit in a PC game.
Third, the best you could exploit out of warhammer mechanism apart from randomness, is the clear difference between civilization. But for this there is starcraft and I'm pretty sure TW can't get to their level.
Apart from that, warhammer universe is cool and diverse, it could produce great PC game but TW has become too fucked up to succed in that task.