Hello all...longtime lurker here, I guess this debacle brought me out of the woodwork, lol.
I was able to use the original coupon early this evening at a Best Buy in my area. I got a Kindle Paperwhite for $69 and tax, so I'm happy. I struck out on Tuesday at another BBY, and at three different Staples stores. Luckily, I travel around my region for other reasons, so I haven't wasted any gas on this.
To those who missed out on Monday (like me), it might still be worth a try if your not going out of your way. I got the feeling it helped that the Kindle was one item over $100, and that I was the only one in the vicinity of the register. Also, this store did not have signs with the coupon "correction" taped all over the place, so I was able to go get the Kindle and bring it to the register and act surprised when I ran into trouble. I complained for 2-3 minutes (politely), then the manager approved it.