After Spider-man 3. (which could have worked very well if Sam Raimi was not pressed to include the character of Venom) and Shrek the Third (with about 10 new characters taking away time and plot from the heroes) Pirates of the Caribbean: At World's End suffers from the same fate: too many characters, too many story lines in one movie. It is not a problem for me that the series transformed from the pirates/horror/adventure genre to pure fantasy by its end; the problem is in this movie we have about ten characters who have their own storyline, their own aims and it's a, hard to follow and really care b, simply too much for a movie (or two movies cut in a half); this many characters should have a TV series not a movie. Of course this also means that the characters from the original have a bit less screen time than they should, while the new characters don't necessarily bring too much to the table. For example, Chow Yun-Fat's character is simply not too well developed and you can see even the writers could not really find out what to do with him. About the 'old' characters: Davy Jones is more interesting now than in the previous installment (and his f/x is even more credible); Will Turner is still not too entertaining (but at least he does not have too much screen time), Elisabeth is okay, Barbossa makes a really welcome return, and Jack Sparrow... Well he is Johnny Depp. I felt his role was overplayed (not by him; by the direction) in Dead Man's Chest; now this is not the case; now he is simply not as entertaining as before due some post-mortal craziness. Actually these 'crazy' scenes are a bit bizarre (but at least this is something really new, not only rehashing old jokes). Compared to Dead Man's Chest: 1. there are less jokes (and still there are some bad and badly played jokes just like in the first and second movies), the tone is more serious which is okay for me 2. no classic fun actions like the one with the wheel or the bone cages; instead of them the last one hour of the movie rocks; very spectacular. 3. between actions and Jack Sparrow scenes DMC had totally boring and senseless dialog's. This one still has lots of quite boring dialog's in its second third but they are acceptable (they could have been trimmed by deleting some less interesting story lines; as I have mentioned in the beginning, this is the biggest problem with the movie).
But unlike Spider-Man 3. or Shrek the Third, the movie is not lower in quality than the previous one; while in some aspects it is even slightly better, for the first two thirds it is a bit less entertaining. Still, quite a good ending for the series.
(By the way, if you are a Pirates fan, watch Sinbad - Legend of the Seven Seas. You will be surprised how many elements were 'stolen' from that movie alone.)
But unlike Spider-Man 3. or Shrek the Third, the movie is not lower in quality than the previous one; while in some aspects it is even slightly better, for the first two thirds it is a bit less entertaining. Still, quite a good ending for the series.
(By the way, if you are a Pirates fan, watch Sinbad - Legend of the Seven Seas. You will be surprised how many elements were 'stolen' from that movie alone.)