If you played and enjoyed Risen you'll probably like Risen 2 as it's a worthy follow-up. It definitely has it's problems but if you can look past those flaws there's a gem of a game underneath and there are plenty of things to love about it.
PROS
Great world and setting
Funny dialogue and characters
Slow but rewarding character progression
Enjoyable and varied sidequests
Great lockpicking minigame
Well realised weopons (the muskets in particular are a lot of fun)
CONS
Very buggy (jittery animations, bad texture pop in, character and environment pass through)
Graphics are mediocre at best
Combat starts off quite dull but does improve (though not drastically)
Occasional, VERY bad framerate drops
Despite it's flaws I'm enjoying it more than many recent games and would definitely recommend Risen 2 to anyone who can look past a games flaws. If you're the type of person who likes very polished triple-a games, however, give this one a miss.