Well,first, I do not believe those screens are alpha or anything, this is the real thing, and while it will probably evolve until release it won't see drastic change unless the game is delayed by years.
Now, if you focus on the main char, clearly you can see the new direction : it's more colorful, colours are more saturated and have higher contrast than in DAO, it's more stylized than realistic, although you can't call it cartoony either.
The armor's model and texture are clearly more detailed than what we get in DAO from such a close up shot. If you don't believe it, take a screenshot of you character's armor in-game from that close and you will see the lack of detail is striking.
What seems like a bad choice to showcase these screenshots is the lighting : everything seems to be under average lighting, so of course when you compare to a screenshot in the tower of Ishal where it's pretty dark with a couple of light sources, it just doesn't give the same feel.
Now, about those darkspawn. The texture clearly aren't a problem, if you look atthe first screenshot, with the hurlock's left pauldron in the foreground, you only begin to see the pixels of the texture, DAO's textures start falling apart from much farther than that. That wasn't really a problem, though, because most of the time you'd have the camera far enough that it isn't noticeable, it's all part of the more cinematic experience, I suppose.
Now the darkspawn design itself. Can't say I like to see the Ogre go almost skinny, though the new skin looks alright. The armors, of course, look very crude, but that's intentional. People were complaining how it didn't make sense for the darkspawn to have armor so elaborate it put to shame the armor the player could wear, this seems to be Bioware's answer. Now the triangular pauldrons may look a little ridiculous but it's just a matter of getting used to it, and at least, when you see a group of darkspawn from afar, you can't really be mistaken about what's coming : spikey spauldrons of vilany = darkspawn hurlock. The one thing that I really disagree with is the mail coif on the hurlocks, it just doesn't go with the rest of the armor. If you're going half-naked with crude spikey plates, you do it all the way, you don't start adding mail on the head only, so either give them some sort of shir, or go head nake, maybe with some sort of helmet.
Finally, the environment, well, although the environment showcased here may or may not be part of the final game (looks like a small test area using actual game assets), it just wasn't the best thing to showcase the first screenshots. I'm sure they have some much more visually impressive environments to show off, so why not put some in those screens ?