Last years' 6700 was due to (in no order):
Many Nebraska Fans
$1 Tickets
Free admission wearing Gold
Free admission with WBB Ticket (they had a game beforehand)
However, I think 7000 is certainly realistic tomorrow. The thought of planning beforehand is a good one; I normally go to Hilton ticket office when it opens. I went to Mason City today for other stuff, used my head, and went to Hy-Vee and got my ticket. Paid $6.90 instead of $5, but probably will be worth it when I see the line tomorrow night.