Slightly less headache inducing than 'Waking Life' thanks to improvements in the computer aided rotoscoping techniques, and really beautiful to look at. But the story and direction seem to have taken back seat to the images, and the movie suffers for it.
After a wonderful opening sequence with a strung out addict desperately trying to rid himself of multitudes of imaginary insects that are crawling over himself, the movie quickly comes to a screeching halt with the introduction of the Keanu Reeves character and his 'camoflage suit' (one of those things that probably work really well on the page, but when you try to visualize it... ug..... - a more annoying visual I have yet to experience), but the suit is a major plot point, so you are forced to endure it on him and others throughout most of the movie.
Robert Downey Jr, Rory Cochrane and Woody Harrelson enliven all the scenes in which they appear, but being only marginal characters they can't save this confusing flick.
Not really sure why it was decided to 'animate' this, it probably would have worked equally well as live action with a minimum of special effects (the camoflage suits and a few bug scenes)