Just went to watch Brokeback Mountain today. I liked the movie, and I thought that it is a good movie, but I don't call it a great movie for the following reason.
Brokeback Mountain covers the time span of 20 years. Some people maintain youthful look for a period of time, but if you drink, smoke and take labor intensive jobs like riding horses, construction, etc., you will look older when you hit 40+. IMO, all (major) characters look too pretty while they go through pretty rough 20 years or so. If this were taken care of, then the movie could be 100% better.