I just checked the price of the bundle and its $295, I don't know if they are dropping it down AND giving the $100 credit. It may not be as good as Walmart's BF deal if the don't.
Oh, they'll reduce it. How much, I don't know - but they always do with the lightning deals. I wouldn't be surprised (but this is in NO way a prediction or any hint of inside knowledge) if they match WalMart's price.
I got a 360 with kinect here the other day(canada) for 299 plus tax but it came with a $50 gift card and $130 worth on points at the store which i used on christmas gifts. Sold the kinect for $75 because it was imo stupid and now have a 360 that cost like 80 bucks.