Report from the frontlines:
I hit the Burbank store at 9:30. They were busy but not over run with people. They had plenty of stock on advertised items; in fact, they were putting out more while I was there. They also were fully staff with lots of clerks who were going out of their way to be friendly and helpful. (The latter, of course, being a major stretch for most of them.)
Obviously, as far as Burbank goes anyway, they're well-prepared for the day.
I bought one of the Seagate 80GB drives so I have the rebate form. If anyone wants/needs a copy, let me know and I'll scan it for you.