Ignore all the critics who opine about a lack luster Pirates 3. Go see it. It is a great summer popcorn movie. Obviously over the top, cgi driven, but clever and fun. Anyone who gave this movie a bad review was expecting way to much -- or thought that because the first movie was a surprising success that the second and third would suddenly be much better.
It's a long movie so try to get comfortable before the previews roll. This is just a very fun movie and a very satisfying ending to the trilogy. The twists, turns and constant backstabbing leave everything up in the air and nothing is really predictable -- and they are so subtle and quick that it probably requires a second viewing to follow everything... That is not something you could say for any of the other 3rd movies out (Spider-man, Shrek).
This film redeems its middle child. Pirates 2 was an elaborate setup for this, so in that way, looking back we can forgive many of its faults -- the payoff made it worth while.