Actually, I liked the movie. It was probably once of the most stylish pieces of anime around at the time and could probably still contend. It also has a wonderful sound track, although I will admit that that is very much dependent on you taste... 'Atmospheric' just doesn't come close.
The catch comes when you look at the plot, especially when compared to the original story. Suffice to say there isn't much of it. At the time the movie was created only 5 or 6 (correct me if anyone knows the actual figure) volumes of the manga were in existence and nobody (least of all Clamp, I suspect) knew where it was going to end up. This movie is a fairly good example of knowing less than a quarter of a 20 volume manga series and having to bring the story to a full close in 1 point something hours.
I won't write spoilers in case there are people who have yet to see it, but the movie has been subtitled XTheTrafficAccident by disgruntled fans...