I think the criticisms come from two things, the lighting (as Maulfan stated) and the over exposure. No, not camera exposure, just the fact that we have really gotten a TON of pics of this guy before it even started to ship. I'd go as far as saying it's Hot Toys' most photographed/promoted figure so far, just wait until everyone gets theirs.
I mean, we saw this at SDCC, there were a ton of shots hi-res and low-res. You could literally see the enamel on his teeth. Then before the specs/pics came up, there was a picture frenzy from plastic enemies.
Gotta take into account that the great pics we got today from the first four or so collectors are super hi-res shots of the head, blown up a couple hundred percent on our computer screens. Of course it's going to appear different and you'll see molding lines. The images are as hi-res as they get. If you'll notice, the figure looks different depending on the photographer. OMG's has some pretty sinister looking shots, while others looks more like the proto, especially the out of box shots.
While I think they tweaked it a bit (the close ups make it look a little different to me, can't put my finger on it(, I think in person it's going to be as good or better than the feeling we all got from the initial prototype.