So, I finished the demo yesterday night with Lucas.
First thing that impressed me was how swell the engine runs and looks. This isn't some clunky NWN2 or AP, this is actually a well optimized engine, and it's even Obsidian's own. Looking forward from more titles using this tech.
Gameplay wise, I wasn't exactly blown away, but I understand this is a Dungeon Siege sequel, so it works. UI is very easy to understand and very transparent, controls with mouse & keyboard work very fluid (don't know why people complain about this). Overall, very good stuff.
Writing otoh is not exactly very stimulating, so far. Okay, it's just a demo, but this coming from George Ziets who wrote the brilliant MotB kinda left me a bit disappointed. Hope the full versions gets better in that department.
The game seems to be quite linear, but I understand that an open world experience wouldn't work very well for that kind of game.
Combat and pacing feels just right.
Overall, not exactly the most ambitious ARPG I've played, but certainly very fun on it's own. Will buy.