Luckily, I got to watch the non-3D version of it... I really do not like 3D movies, although this was another movie that was filmed specifically for 3D, so even when not watching it in 3D, you can see aspects of it that were made to showcase the 3D technicality.
Anyway - the movie was okay. The storyline was pretty thin and uninteresting. Not like the first ones in the series where the storyline was at least intriguing because it was about pirates. This movie wasn't really much about pirates, but instead was more about myths, legends and magic. Just a generic adventure movie that happens to have pirates as main characters. It didn't touch much on the background storyline about Jack Sparrow, and the only 2 recurring characters other than Jack Sparrow were Barbosa and Gibbs. This movie confirmed the stereotype that sequels are no good.
The action in the movie was pretty good though. Some cool swordfights, nice CG on the ships and the mermaids. Cool scenery and stuff. If you like 3D movies, then that stuff would probably be a great selling point for you.