In the final days, I think Adorama had the better of the deal on the 70-200 IS II USM at $2069 vs $2074 - BH went up a tad at the end. But BH has better UPS shipping rates.
The question on Saturday evening is a good one. I called them about that Wednesday (I was having some administrative issues with BillMeLater at the time) and did not get a very reassuring answer. While the online may be up, is the store going to credit the order then? (edit - I see JR says it should work - I only talked to a sales droid)
I purchased the IS II USM Thursday and got it today UPS Next Day. Not sure I'm happy with UPS though.. - with a hole that went through both the shipping carton and a bit through the Canon box. Fortunately I dont see any mark on the lens case and the lens works correctly. (Damn I want a new box now!)
You may want to check around and some other sources that may still be open or open Saturday. Yeah, they may charge more, but if you want that lens, $300 is your base savings.
Heck, given the shipping issue, I might have gone local and ate the sales tax.