It is a bit of a dumb action movie, in many ways. A guy with a sword takes on an entire flotilla, if I recall correctly. The coolest moment in the entire book involves somebody saying "I'm sure they'll listen to reason" and then pulling out an enormous gun labelled "REASON". So if the movie turns out to be full of dumb action sequences it'll only be consistent with the book.
Another major flaw of the book, as written, is that it has chapters upon chapters of exposition which are basically dialogue scenes between Hiro and the librarian program. Most of the actual overly complicated plot stuff winds up getting explained in these scenes.
The third problem with the book is a rather dated view of the future... or by now a rather dated view of the immediate past. Both Hiro and the other dude are reasonably young guys whose fathers fought in World War 2, which puts a fairly stringent limit on how late you can possibly set it (unless you play around with which war it was; I think the fact it was WW2 was fairly vital to the backstory though).
Anyway, I'm not against a Snow Crash movie at all, I'm just pointing out that it needs some serious work to be adapted, and that may wind up throwing out some of the bits that many people like best about it.