Well, there's no $50 rebate at Amazon, but I've been watching to see when they're supposed to ship my pre-ordered copy. Answer: Oct 28. Being a cheapskate, I'm getting free-shipping (and slower - so I can listen to everybody's gripes for a few days before I really install it.
Anyway: some time today Amazon increased their discount from $0.90 to $10.00. They won't tell you the price on the description of Panther (explaining "The "too low to display" message indicates an additional discount is in effect, and this discount is calculated in the Shopping Cart.")
Here's the weird part: The price on my "Order Status" page had *not* dropped. I didn't trust them, so I canceled my order and re-ordered a copy. My new order shows the new $119 price. Shipping date is now predicted: Oct 30.
Anyway, anyone else on a shoestring budget who wants to wait a few more days for an untaxed/free shipping/discounted edition... you may need to cancel any previous Amz order and re-order.
BTW: Also noticed that Panther sales rank at Amz went from 20-25 a few days ago to 11th early today to 10th now. I think they're starting to fly off the shelves before they land!