For me it will depend upon what is going to be on sale and the tenacity of others. In an experience similar to paketel's, people seem to start lining up 3 hours earlier than the year before. Last year I arrived on line @ 5pm Thanksgiving day and was 12th in line. (the first 6 people in line arrived @ 1pm in an RV and had their T-day meal in their RV.
I enjoy the Black Friday experience for a variety of reasons, but if the tough economy causes more people to be more determined to get in on these deals, I can see the dynamic of things changing this year. There was a camaraderie among the fellow knuckleheads who are crazy enough to camp out for Black Friday.
In the past, when economic times got tough, there was a more somber, less jovial attitude by those camping out. The number of people on line 12 hours before store opening will be a good indicator.