Without going to much into the film because I don't want to spoil it, I think they should have created more of a background for the story line. IMO it would have been better if they explained how and why everything was happening. I understood the film but the story line was just left wanting...
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...My brain's always wrapped...
No, I think this movie borrows from Terminator 2 more than anything else. You've got two beings which look human, but are actually much more powerful. One is good, the other is evil, and at the end, they have a big battle in the middle of a factory, complete with hot sparks flying everywhere. There is the element of an alternate world which only they know about (the future war in the Terminator movies, and the "multiverse" in The One). And that flying machine you see near the end looks exactly like the flying machines in the future war scenes from the Terminator movies.
Still, I liked this movie, due to the fact that it was short, fast paced, and did not have that awful wink wink, tounge-in-cheek style that plagues so many action movies today. James Wong did a good job keeping the tone serious. And, unlike a lot of directors (*cough* Ridley Scott *cough*), he knows how to shoot action scenes so that you can actually tell what the heck is going on.
EDIT: Oh yeah, I almost forgot. I noticed there were a couple of SFX shots which appeared to simply be ordinary shots that were slightly sped up. They had some odd motion artifacts. They looked almost like interlaced 60i video that had been transferred to film. One of the shots that stuck out the most took place when they were in the hospital, and they heard the gunshots upstairs, the camera swings around Carla Gugino just before she says "Gabe". Another shot was a close-up Jet-Li's feet, when he was fighting himself on the catwalk at the end. Both shots had a very interlacy, video-ish look to them. I've noticed that sort of thing a lot the last few years. Some of the action scenes in Crouching Tiger, Hidden Dragon had a lot of that. What causes it? Is somebody at the SFX houses going cheap and using a camcorder to digitize the film? I know film scanning is expensive, but come on! 
This one had promise but failed to live up to it. Sure the visual effects were good but, what else would you expect that is what all their budget went to? There was no plot development at all. The basic plot was good but that was as far as it went.
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-Life is but a walking shadow, a poor player that walks, and struts its hour upon the stage, and then is heard no more. It is a tale told by an idiot. Full of sound and fury signifying nothing.
It is said that this film didn't live up to its expectations. I see a lot of that in all these threads.
I think we all see too many movies and most it seem dont particularly like movies in general.
It goes like this, I love pizza. I have my favorites, and I have the kinds I hate. BUT, I know that I HATE for my own reasons, and not just because it really is crap.
Same goes for movies.
WE ALL have differing tastes, but it seems that our tastes are starting to sour. I havent seen but a few positive reviews here at all.
WHY I BOTHER WITH THIS?
BECAUSE I happend to thouroughly enjoy this movie. Yes of course it borrows from a few specific movies. WHat a way to pay wonderful homage to its predecessors. Just because one movie that did it first doesnt mean that no one else can do it! Do we do that to every movie that comes out in SCOPE? NO of course not. What about COLOR? NO!!
Why i like this movie...
IT is simple. Short, sweet and simple. NO it doesnt go into grandios explanations, it just tells you a few things, moves to the story, kills a few people, dazzles you with its special effects, and moves on. THat is a good movie. No it wont win awards, but it packs my theater every night.
DOnt get me wrong, i dont get down on anyone here, I just remind you all that movies are meant to be a fun joy ride into a non real world, so we can escape the doldrums of our dreary lives. When we expect to be wowed to a pre determined set of values, we will always be let down.
I just let the storyteller tell me a story. If its good, i cheer, if its boring I sleep. IF ITS BAD, I call it star wars episode one.
Dave