Great fun, go see it. LOTS of Johnny Depp(s) (you will see what I mean). Also, a tip, force yourself to sit through the twenty minutes or so of credits because there is additional film after the closing titles roll and it is NOT outtakes and will be germaine to Pirates IV (currently filming).
Also, in my peculiar version of six degrees of separation, I spotted Kevin McNally as Mr. Gibbs. I was fascinated with Kevin as Joseph Buquet in Phantom of the Opera. We have just connected Johnny Depp to Patrick Wilson via Kevin.