It looks ok, Tails' model bothers me. Can we have a sprite look at that up close like Sonic's? There are probably more problems with it than I can see from the tiny perspective right now but what pops out at me is; His muzzle is too thin, needs to be raised (and made more canine, like his official art) his color is too brown, needs some red tint, his eyes are too circular, they need to be longer, browns more raised inward and slant sownward as they go out, pupils are too small, that's a bad position for his Tails by the way. Try basing them off the frame that came before it so they don't appear stretched. I don't know why everyone does that frame for them, that's not the one where they're relaxed. And he nas no smile. If one is added, it needs to be in the middle of his mouth since that's where classic Tails' smile was. (See: Sonic The Fighters) (again, refer to the Japanese official art, not that monstrosity that was AoStH Tails. (Shut up Fanboys, you all know that model looked nothing like Tails. At least American Sonic was the right color and still resembled Sonic, the only resemblance for AoStH Tails was having two Tails, even his shoes were wrong, just look at the DVD. The rest looked more like a squirrel.)
Background looks nice but needs more colors and less abuse of the Burn tool (which is how this looks now) and the foreground needs to look less like a vector of an 8 bit Nintendo game or a papercraft but this is good for a mock-up. Certainly miles ahead of Sonic 4's art design if only because the classic models are present.
I actually love the vector shading, it's very contemporary, if that word can be used, I don't think realism should entirely apply to art direction past making things look like the source material and move correctly.
I have problems with the Tails model but I really would like a sprite view of it, it looks better than anything else, certainly better than whatever you would call S2HD's Tails mockup, this one reminds me of the older S2HD mockup, which looked more like him.
QUOTE (Polygon Jim @ Sep 4 2010, 05:08 PM)

Fast shitty Photoshop.

I think it would look better if changed to be more like this.
I like your photoshop better, American Sonic is a really bad reference to go by unless you're making a game based off SatAM or something, but it's better to go with the better art direction for anything else. (And by "better" I mean "Wasn't photoshopped from Mickey Mouse or drawn in our god-awful Toon-style which looks awful on Sonic and makes his proportions all off.)