For me personally, it would have to be the Skyrim line. However, I only waited an hour and fifteen minutes compared to many who waited the entire day. I'm not sure if I was just lucky or if I just lined up at a time when a super special panel was on; I went around 4 -5 ish on Friday, which might have explained it. I also went to the Borderlands 2 line on Sunday around 3 - 4 pm and the line was definitely only an hour long, which surprised me as well since it was one of the most popular titles at the expo.
What about you guys? This was my first PAX and with all the complaints surrounding the amount of lines at the expo, it honestly didn't bother me at all. It would also help if you posted the time and the day that you went to line up for [insert game title].