It really is too soon to tell. It's just a lot different from what most people were probably expecting. It's clear that they want to distance themselves as far as possible from the last series, which to a large number of people is blasphemous, because for a while yet, you're still going to have a majority of people swearing "Nolan, Bale and Ledger's stuff is never going to be topped." Just like some people still swear that Burton's stuff was better, even though... y'know... it wasn't.
It'll probably be fine. I don't get the obsession with him "needing" to have the permanently frozen grin, though; he actually doesn't always have it in the comics, it's entirely dependent on the artist. Sometimes he's "stuck" that way, sometimes it's a scar, and sometimes he just does it because he feels like it. Even in the cartoon version everyone's so obsessed with, he didn't have a permanent smile. It's whatever. The only thing with me is that the tats are a bit much, but even if that part is real they'd probably only be visible in one scene anyway.
I'unno, it's alright. Could be better could be worse. I'll admit I'm a little biased towards Ledger's take, but eh, gotta move on sometime.