I like how everyone's arguments against criticism of the artwork don't even defend the art or say it's good. They all just say we aren't allowed to be critical and should automatically like everything DT put out or that our expectations are too high or that the art isn't important.
I notice that tends to happen with DT (not necessarily just here, BTW). The way I look at it is that if the band wants to do something "above and beyond" or not within the norm, they definitely should get appreciation for their efforts, but they also must open themselves up for criticism to those things. It ideally should be constructive, rather than "this is terrible," etc., as I don't defend, at all, what would be constituted as bashing.
Personally, I'm thrilled by the concept, believe that the still art is amazing, love the world that they have built with the characters/map/etc., and can't wait to receive the physical goodies in the boxset. However, I also recognize that the animation in the trailer is subpar. I'm very optimistic, as Blob, I believe, indicated that the trailer is not indicative of how the art/animations will actually be used in the live shows.
In the end though, unlike a movie, or even a video game, Dream Theater is about the music. I do think that some people are going overboard with how much they are letting the extra materials impact their enjoyment of the album cycle, when in reality, those that hate it may love the album, and someone like me that really enjoy this extra stuff could actually end up disliking the album.