Though I was not able to play The Witcher 2 for long, as my GPU is seriously failing at this time, I was able to get a good two-hour glimpse of what the game is about.
The very first thing that came to mind is: this is what Dragon Age 2 should have been.
From my point of view, both DA2 and TW2 had very similar changes from their first installments. Both games are now much more console-friendly, as someone would call it "dumbed down", but this is where DA2 fails to deliver any kind of excitement, and TW2 gets it just right on the spot. The graphics are marvelous! THAT'S how environments should look like, Bioware! Not a flat dirt road with two trees, each having three branches! DX11 my a$$!
Despite the fact that all the old characters look almost completely different, I find nothing wrong with that because they actually look better than in the first game (I found all the characters kind of similar before, if you look closely at their jawlines, cheeks etc.)
The story upholds both old and new excitements and curiosities. The voicework is hilariously funny and very well done, and as far as I can hear, everyone but Geralt got new voice actors. Coupled with new visuals, it does get kind of weird at first, but there are so many things going on in the game that there's simply no time to concentrate on that.
The game music and the official soundtrack are EPIC!!! The very first song from the intro is a song called "Ой Ти, Петре, Петре" from my favorite Polish (psychedelic folk) metal band "Żywiołak"; needless to say that I was completely shocked hearing them in the intro. Pleasantly, of course

I have to say that I was skeptical when it came to the soundtrack. I didn't think that it could be any better from the first one, but I was completely wrong, and I'm happy about it! 8D
Animations are amazing! Walking through doors, climbing ladders and stuff is great. One small complaint would be the camera movement during battles, but I got used to it. The game is also very challenging and realistic, which is fantastic; simply one of those things that make an RPG game incredible. The battle styles may have changed, but leveling is definitely more exciting than in DA2. As a realistic game, it comes close to hack&slashing, but it stays on the good, fun side nevertheless.
The inventory screen is kind of messed up for me, it gets complicated at times, especially when I need to buy/sell stuff; that definitely could've been improved. I've also heard complaints about drinking potions, which is only able during meditation, but as I've read the book, I don't mind it (much); the game definitely stays true to the book in such aspects.
I can definitely see this game as the RPG of the year, since *trolling on* Bioware definitely won't have enough money to buy off reviewers for the title *trolling off* xD
Overall, the game is something you shouldn't just play, but also cherish each and every moment, especially if you bought that colossal version that comes along with everything, and then some!