The hate this game is getting is unreal and so hyperbolic. I think many here played themself dead on Dark Souls 1 and now every little change is drama. I enjoy it as much as Demon's or Dark Souls. For me it still is Demon = Dark1 = Dark2 (so far).
I think this is pretty much the Uncharted 3 effect. People held up Dark Souls 1 as the Jesus of games and now the second game is still very good but not another coming of Christ and it is getting trashed.
I'd say Dark 2 is awesome but not quite on par with the first one. It's made quantitative improvements in some areas, like with higher highs in the graphics department, and improved animation and nice cloth physics. There's also "more" in a lot of regards -- more areas, more items, more features (dual wield stance, more stat types). But it's missing some of the "X factor" from Dark 1. That special something. That special unity of vision.
Imagine you're a band making your first big album, and you put everything you've learned into it, and you have all kinds of ideas you've been working on and nurturing and everything goes into that great album. Then you're asked to follow it up. And for some reason the lead songwriter is bailing and some new dudes are coming in.
You've got a great follow up album, but yeah, it just doesn't have the same "special something" that the previous one had. IMO.