To add to my comments in the Fantasy group, I will say that I thought the scenes in Davy Jones' locker with Captain Jack and his "crew" were hilarious. In fact, the movie did not come to life for me until we saw Jack. I thought the twist for Tia Dalma was good. I was so freaking happy that Barbossa came back - the verbal (and other) sparring between him and Jack are part of what made the first movie. I love how most dreams came true, and the visual effects were simply stunning and should win another Oscar win those awards roll around.
Is it the best of the series? No, it's probably the worst, but not by much, because I think the series as a whole is a strong one. On my patented ratings scale, I give this one an 8 for minor flaws but still very good: the flaws were the convoluted story (easy enough to follow if you paid attention but definitely jampacked to the point of being slightly detrimental), the long running time (less Jack hallucinating would have shaved at least a few minutes), and too much Keira Knightley. It passes the test though. This would be a fun trilogy to watch as a marathon, so I think I would have to buy it. Plus - complete movie sets are my thing.