Finally saw it. Worth a rent for the creature designs/effects and humor. Nothing special otherwise.
I enjoyed the heavier dose of humor this time around. The moments weren't as poignant as those in the first movie, but they did make me laugh and there were a lot more of them. The creature effects, like everyone has said, were delightful and very fun to watch. The Troll Market is a nice 2008 version of the Mos Eisley Cantina (or Jabba's Palace, if you prefer). Kudos to del Toro for keeping most of the creatures practical, effects-wise. I didn't really care for the handling of Johann (his voice or his personality - his final line was particularly bad). It was odd at first hearing Doug Jones' voice for Abe (instead of David Hyde-Pierce's), but as the movie continued I got used to it and thought he did a great job.