OK, I saw it. Wasn't impressed, though my Dad + sister liked it a lot, which surprised me, I felt they would hate it more and I was embarassed the whole time since this was a movie I was pressuring them to go to and they paid this time around. >_>
First things that bugged, as omae mentioned, the "white boy saving China" bit was lame. It was already bad enough the kid was a low-level weeaboo, but to be so utterly pathetic just made me go "uggh". He got better as things went along but his total foreign-ism just prevailed through the movie. Like, with the she-assassin. They had a lot of "romance" scenes, but they basically involved him looking at her lovey-dovey and her thinking of revenge.
Another bad thing was "kung fu". As I understand it, kung fu isn't a martial art, it's a way of life. Everyone - from the scholar to the monk - calling the fighting techniques kung fu just buzzed off in my ear all wrong.
Everyone speaking English and then Chinese struck me as weird. They should have just spoken Chinese and everyone have subtitles; it was hard to follow the English when the character's weren't shouting.
Not much comedy, I was expecting The Mummy Returns here in terms of quirky laughs with good action, but there were a few good scenes, primarily when the monk actually came about.
Plus-wise, action sequences when there wasn't CGI were very good, my attention was held (unlike with, say, a horrible movie like Drillbit Taylor: Budget Bodyguard) for a looooong time. Chan was arguably the weakest I've seen him in this movie - I've loved his early work, but disliked Rush Hour and Shanghai Knights, with Around the World in 80 Days (imv) his jump the shark moment. Most Chan movies revolve around him as the star and his insane martial arts as the focus, but the CGI and Jet Li stole his thunder.
I REALLY liked the monk, best part of the movie with the great twist at the end. I'm totally satisfied with what happened to him.
Overall? 17/20. Not a bad movie - story was rather mainstream and predictable, with a few twists, but otherwise enjoyable. Best experienced if one turns one's brain off, if possible. I couldn't in this case, so that ruined the experience.
For reference, I'd rank The Mummy Returns at a full 20, The Mummy at 19, Van Helsing at 18, Pirates of the Carribbean: World's End at a 14, with the original Pirates at 19 and Pirates II at 15.