Well, if you look at the game, you'll know that it'll look quite a lot like BO3 in many ways, though that's not much of an issue. I actually think the game will do well, but since there won't be a campaign then it may stump a few COD fans out there who enjoyed the campaign.
I personally think the game will be great in it's own ways aside from the other three games. The new game mode Blackout sounds exciting but let's try not to build to much hype for it. There's still that heavy chance of the game failing in many ways.