At least as good as the first one, if not better. Warning: The film is part II of what is now going to be a trilogy.
What do you really need to say about this movie? Depp? Good. Knightley? Cute. Bloom? Girly as ever. There's plenty of sword- and gunplay. Go see it.
What's interesting to me is the context of the movie: At the very beginning (minor spoiler alert) we learn that the East India Trading Company (East India? In the Caribbean?) is moving aggressively to swallow up trade in the region, and tamp down on both piracy and independent traders. At one point, the EITC manager says something like "the world has gotten smaller. The empty spots at the edge of the map of been filled in." For me, it was a very evocative moment, when you consider that the period of the movie is really the first period of true globalization as we know it - when European empires were so large that the sun never set on them. (Purists will tell you the sun still never sets on the British Empire. These purists probably wish Mountbatten had never given the Jewel in the Crown back to the punjabs and their half-naked fakir.)
And saying the world has gotten smaller - isn't it a way of saying the world has gotten flat? Except that what Thomas Friedman sees as wondrous, Pirates sees as lamentable. The power of capitalist hegemony - in this case, wielded by the unyielding colonizing force of one of the world's first multinational corporations - is imposing its will on a wild, untamed region of the earth, incorporating the edge in to the center, with all the violence that entails.
It may sound like I'm exagerrating things here, but I swear to God Disney's made a movies with Marxist themes to it. If I really wanted to, I could probably write about how Jack Sparrow represents the worker trying to seize control of capital through violent revolution, and that the freedom of the open ocean is a form of permanent revolution, but that's unnecessary.
You go see it, then tell me I'm wrong.