I picked up a copy last week for $19.99 and will go back and have them credit me for the difference tonight. The packaging I have ends with "1". Glad to see that the $14.99 price panned out. It was on the front page at the very top of the Sunday flyer.
I was at Target (in Omaha) yesterday evening and they have BTTF for only $19.99 for the trilogy on BD. I assume the sale ends Saturday night. It was on a major endcap with some other new releases.