I was a little reticent about this one. Not only do I dislike Tom Cruise as an actor, but I have generally found Michael Mann ("Miami Vice," "Heat," "Ali") self-indulgent and overblown, with pseudo-intellectual trappings that never quite pan out. Even "The Insider," which is probably his best film, didn't quite hold together as a great work; too much mumbling Russel Crowe for my taste.
That said, Mann has a good eye and genuine passion. As a close comparison, Mann shares attributes with Oliver Stone, in that both tend to make didactic movies simmering with real personal feeling. I would submit that Stone's the more interesting filmmaker; he takes bigger risks and is consequently sometimes more annoying. But with both Stone and Mann, whatever their faults, you never feel you're in the hands of a hack filmmaker.
"Collateral" suffers from all the usual Mann problems, but is worth a look on DVD for the terrific lead performance of Jamie Foxx, some nicely-nuanced supporting work from Jada Pinkett Smith, and the general feeling of malaise surrounding L.A. and its environs. The story holds together pretty well, although the first half is far more interesting than the second (how often this happens!). Mann's propensity for cheap philosophising weaves in and out of the picture, but -- if you don't take it too seriously -- there are worse ways to spend a couple of hours.
On the other hand, if called to the mat I'd recommend you skip "Collateral" altogether and check out this, this, or this. That's the great thing about the DVD revolution (and, especially, Netflix). With so many brilliant films to choose from you don't have to settle. Ever.
ADDENDUM: I'm not at all happy with this review, but I'm trying to be disciplined about saying something about every film I see, as a way to stretch my critical muscles. The problem is that with "Collateral," I couldn't really figure out much to say. I kind of, sort of, liked the film, but it left a distinctly unhealthy taste in my mouth -- like gourmet pastries made with vegetable shortening rather than butter. Mann just tries so hard, and has so much talent, but the film is ultimately a bit dishonest and a bit sleazy.
Writing in "The Village Voice," critic Michael Atkinson nailed the best review I found anywhere. I quote:
...Mann, like Democrat politicians, has bought into a moneyed system that allows only for half-successes and paltry ambitions....Collateral is a slim drink of thin beer, remarkable only as evidence that Mann might have a modern masterpiece in him if he were cut loose and allowed to roam around in his own obsessions.