I found myself pretty impressed by this, actually. I wasn't expecting much out of it, but I was honestly entertained.
It's clearly a kids movie, so you have to look at it like that. Of course, it's not PR-level kids. The action and language are a few steps above your average childrens adventure film, which gives it an edge.
The thing I loved most about this movie is all the references to classic kung fu films. And I don't just mean the stuff the white kid likes in his own world. I mean they literally filled the actual story with elements to well-known kung fu films.
The most awesome element to me was The Witch, who is clearly an homage to The Bride with White Hair, right down to her wolf-born origins and her distain for all men. As well as her bone-splitting whip.
"She will kill you, Witch!"
"Not if I kill you first, orphan bitch!"
Best. line. ever.
Kudos also for mentioning the No-Shadow Kick, the Buddha Palm, the Monkey King, and a whole boatload of others I'm not thinking of at the moment.
I'm not a fan of Jackie Chan, or his comedic action style, but it was still quite fun to see him do his thing, as the Drunken Immortal, and playing off of Jet Li's monk character. The double roles both stars played was amusing as well.
The movie reminded me more of "Warriors of Virtue" than "The Neverending Story" (as some people mentioned). It too was a movie about a white kid that transports to Kung Fu Land. Except there were no talking animals or extremely blurred-out caucasian villains.
I'd recommend this movie for kids (who don't have hyper-defensive parents), actually. I'm so going to buy this when it comes out on DVD. It was a fun kids action movie.