Dragon Age 2 is definitely a wonderful gaming experience in general, but it will alienate it's fanbase.
Let's start with the good.
Much better graphics than it's predecessor specifically on the console versions. Although, they could certainly be better. Most DA fans will be thrilled at the improvements. Spells look more vibrant and detailed, textures aren't as sloppy and ugly, and the game has some pretty scenery.
Great character development, specifically for your character, Hawke. Lots of different ways to go about the story and immediate gratification for the decision you make. I can tell you this, the replay value is great. This game will have you creating multiple characters and playing through before you even finish the game with your first one.
Stylish new gameplay that features a more console friendly hack n' slash-esque mechanic. This is good and it's bad. It's definitely a lot of mindless fun.
Great, epic soundtrack that keeps everything in motion.
Tons and tons of hours of quests and things to keep you busy.
Now the bad. While the good in the game really makes this worthwhile, the bad will definitely alienate fans.
Firstly, this game is way, WAY too easy. The new console friendly gameplay makes everything less strategy based. PC gamers in particular will be annoyed because it is a far less tactical approach. In making it more accessible to console gamers, they messed up what made the first game fun in the first place.
The games story is largely disjointed as well. The quests you'll be doing won't have anything to do with the plot and they don't have a driving force. You just do them because that's how you advance the game. It's unfortunate because the illusion of you doing what you want to do to keep the story going is lost. Not a deal breaker because there's plenty of story within the game. Everything is just not as connected as it should. And speaking for a moment just about the story in general, it's a good story and warrants your attention. But, for the most part, the development of your character is more of a focal point than the actual story. Kind of like the TV show Lost. There's a lot of different things happening but what's important is your characters reactions more than what's actually happening.
The supporting characters aren't as good as they could be. They don't command attention, though they are all unique in their own right. So no they're not exactly the deep, vulnerable enigma of Leliana nor will they make you laugh out loud like the lovable Alistair. They are solid and interesting enough for you want to explore their backstories, they are just not exceptional and don't stand tall against the standard set by BioWare.
A TON of things are seemingly stripped down. I'm not sure what the deal here is, but in terms of interfacing with the game, the first one is far superior.
There are other minor details that may or may not annoy you, but they seem trivial when I think about it. So those are basically my biggest complaints about the game. I have a lot of good things to say about the game. I think it's still incredibly immersible, beautifully written and soundtracked, and has enough to do to give you your money's worth.
But there will be negativity because of the direction they took the game in. I will say, while the hack n' slash addition is nice, I much, MUCH prefer the old tactical style. It's very clear that they decided to cater to console gamers and that will definitely piss people off. For what it's worth, it's still very enjoyable and even if you don't buy it right now, I definitely recommend playing it at some point.