I quite liked it, though I couldn't finish it. I plan to get back to it with all DLC one of these days.
Expect a huge game with a ton of filler content - but also quite a bit of story content.
The combat system is both good and bad, and is definitely easier as a ranged character. The AI setup is simplified from DAO - but it actually works pretty well for the most part. It's key to configure this to get a comfortable experience. Forget about micromanaging your party members, or you'll go crazy from the terrible combat UI.
Best part of it, I find, is the beauty of the world and the visual variety between areas. Exploration is so-so, but I didn't feel actively punished for it like I did in TW3. You'll progress and find useful things when exploring, unlike TW3.
Story/characters are both decent for a Bioware game, though I feel it gets bogged down in political stuff that's delivered without much emotion. Definitely not on the level of TW3.
Loot and progression are both better than TW3 - but crafting is amazingly full of grindy busywork.
Much of the interface is pretty atrocious. In my opinion, the interface in DAO was much, much better in every way.
There are a few "respawn areas" where creatures come back literally as you wipe them out. I'm still undetermined if this is actually intentional - as it's painfully bad design.
In short, I'd say it's definitely worth a try - but it's far from perfect.
For huge open world RPGs, I'd rank it just below TW3 and a fair bit below Skyrim. Better than Morrowind and Oblivion, though.
IMO, obviously.