I've been playing in the Neverwinter beta today and I've got to say its a beautiful game. Compared to Turbine's DDO's city of Stormreach which never truly felt like a city, the city of Neverwinter created by Cryptic feels like a living breathing fantasy medieval city.
The few dungeons maps I have seen so far are very well done. Very atmospheric, filled to the brim with stuff, non repetitive (which is a feat) and laid out much better than STO's style of room, long passage, room, long passage, room layout.
The only thing that stumped me a little is the class system and class abilities. Part of it stems from me know very little about 4th edition D&D rules. All classes only get to use 3 at-will abilities, 3 encounter abilities and 3 daily abilities? Also, I'm not getting why we're picking specialized classes at character creation time. For example, if I picked the class Control Wizard at character creation, does it mean I can't be another type of wizard in the future when Cryptic adds more wizard types? That just seem like a very strange game design.
Overall, I think Neverwinter will be a sweet game to play if I wasn't already committed to STO.