I live in Arizona and I've been doing BF for years now; for 3 out of the last 5 years I was in the top 10 to the door for best buy's BF.
Things have changed DRAMATICALLY in the last 5 years. Year 1 I went to best buy at about 1 AM the morning OF black friday and ended up just rounding off the top 10 people in line. Year 2 I went to BF at 10:30 PM the day before and was about 3rd in line with my group. Year 3 I skipped (trips). Year 4 - I went at 4:30 PM the day before right after I finished eating and I barely made top 10 (within seconds of another group). Last year I made a choice to not go even earlier because I still wanted to eats dinner... so at about 4:00PM on Thanksgiving again last year I went to BB to see over 200 people in line.... I drove to the next closest BB to see at least 100+ still in line.... drove to the next and by that time all of the locations i went to had over 150+ in line. I finally found a circuit city at about 7:00 PM that had only 15ish in line so I jumped in.... counted up ahead of myself to find that only 3 ahead of me wanted their doorbuster computer... guess what (they only had three) I was really upset because BB typically has at least 10 items minimum for even the best doorbusters so I was very pissed after waiting all night.
Two morals to the story:
First off... NEVER do Circuit City black friday... I tried them once out of desperation last year and even in the top 15 I got royally screwed by their crappy doorbuster quantities.
Second, for some reason BF is turning into a competition amoung the populus.... everyone wants the best deals and is willing to forget about thanksgiving to have them. This year, if you aren't in line by about 10:00 to 11:00 AM on Thanksgiving there is no chance of getting in the top 10 for BB. I personally will only wait in line if I'm in the top 10 again because after getting screwed over, I will only wait for "sure things". Hand warmers are your friends if you are willing to wait through a full night by the way.
This year... I'll probably do a drive by after eating to make sure the lines are already long but if they are for BB I will be sitting out BF this year for the first time ever (aside from my trip) as it just is starting to become not worth the trouble =p.