Good, not great -- does not have the repeatability of the original trilogy.

Rating: 6/10 (23 May 2011)

Admirable attempt to create a new adventure in the Pirates canon with no egregious violations but certainly a host of minor infractions. It's fun, sometimes funny, with some favorite characters as well as a few new faces and succeeds at entertaining even as it falls short of it's venerable history.
First the GOOD: Johnny Depp, while not quite as out of balance or odd, still delivers the quirky pirate we've all come to love. Geoffrey Rush also reprises a favorite character with relish and aplomb. Ian McShane as Blackbeard has surprising presence and I enjoyed the mystery and intensity he brings to the role. Also good are a few good action scenes, some funny moments as Barbossa & Sparrow attempt a daring heist and are captured, and the interesting twist on mermaid folklore.
Another great moment was the inclusion of a true classic scene from the Pirates of the Caribbean ride - the "Skeleton on the bed with a magnifying glass". It was a joy to see they're still working in elements from the Disney ride that launched this billion dollar empire.
The NOT-SO-GOOD: The two primary offenders happen to be the dialogue and the land-locked conquest. First of all, this is a Pirates movie, and that should mean a lot of action on the sea, canons shooting, fighting and outmaneuvering and the mystery of discovery. Instead, we spent at least 3/4ths of the movie getting prepared to set sail, or searching for the Fountain of Youth. Oye, ye Land Lubbers!
The second major problem is the dialogue doesn't have the punch, or the comedy worked into the original. There is too much exposition about the quest, and everybody seems to already know where the Fountain is. Jack Sparrow is more coherent and succinct, with less meandering and fewer odd word choices. And I think we miss out on a lot of comic potential without the two bumbling sidekicks or a love triangle involvement.
The interaction between Sparrow and Angelica (Cruz) is never quite believable. We don't sense Jack actually pining for her, nor does Angelica seem any bit entranced by Sparrow. She is overly dedicated to her father for reasons not explained or believable. I can't believe this... but I miss Keira Knightley's internal struggles and wish Cruz had more of that conflict.
The movie definitely suffers from the lack of a true good guy (ie. Will Turner) and a true bad guy (ie. Davy Jones). This setup had allowed Jack Sparrow's self-serving nature to be showcased, moving on a whim to whichever angle served him best. In Pirates 4, Jack Sparrow has taken the "good guy" role, which doesn't fit him quite right.
CONCLUSIONS: While it's not a bad movie and I was happy to see it, this movie is going to be more sharply criticized for its shortcomings. Too much land-trekking, more mundane expository dialogue, too light on comedy and not enough discovery.
It's a fun ride, but not repeatably wonderful like the "original trilogy" (which is becoming a more common phrase isn't it?)