I just finished playing the demo, and I can't say that I like all of the changes that have been made from Origins.
One thing that I have been nervous about for a while is the switch to a Commander Shepard style protagonist. In this, my worries seem to be for naught, because it didn't turn out too bad in this game. One thing that did turn out bad is the "dialogue wheel" thing with the condensed dialogue options. This is one problem I've always had with Mass Effect, the condensed version of each dialogue option just fails to convey the complete meaning of the full voice acted version.
Another thing I don't like is the graphics. Somehow, they managed to make the graphics even worse than Origins. The environments are barren, with little to no vegetation or clutter. The characters look about the same as they did in Origins, just more stylized and idiotic looking. The character animations are also too stylized. Too many slow motion leaps through the air.
Origins wasn't particularly original, but it had a certain harsh realism that I really liked. Dragon Age 2 is just too stylized in a pathetic attempt to be "cool".
But I don't mean to imply that everything is bad. The gameplay is mostly the same as Origins, but improved in certain areas. Combat is much more refined and brutal. It is somewhat easier than Origins, too easy for my tastes. But the demo doesn't let you increase the difficulty, so that will probably be better in the full game where you can. The story... Well, there isn't enough of it in the demo for me to be able to judge it fairly.
Anyway, this is all still only judging from the demo. I may think differently about some things once I've played the full game. From what I can see it will be a very good game in it's own rite, but it just can't touch the level of awesomeness of the first game.