...Last year people were lined up about 12 hours ahead of time for the 360 launch outside of the Best Buy that I work by, and if we all remember, it was a very cold November last year in Michigan. If it is cold where you are, I highly recommend bringing a tent if they will let you, and maybe an electric heater if at all possible. Sitting around and not doing anything only encourages sickness, so stay active, or if you choose to sit, stay warm. You wouldn't want to lose and fingers so you couldn't play PS3, right?
...The last time I stood and waiting for anything was Halo 2, and that obviously was quite some time ago. In that story, I had two pre-sale parties to go to, one at the local EBgames with some friends of mine around 9:00 PM that night, and the other at the Best Buy (where my Pre-Order was waiting) with other friends. I showed up at 10:30, and stood in line (I was second) for an hour and a half in 25 degree weather in nothing but layers. I froze to death, but it was worth it.
...Would I do it again?
Only for Halo 3, man...