I was just going to mention the same. I asked my DVC guide about upcoming incentives. He did say he doesn't expect them to be better, but he mentioned that since my Direct Contract purchased late June won't close until late September at the earliest, that if the newer incentives happen to be lower, that I can request to be repriced since my contract will not have closed.
He says it won't close until all money has been collected, or financed. Since I requested to pay by credit card over 90 days/4 payments (immediate deposit, then 30 days, 60 days, 90 days) to spread out the payments on my Disney Visa, my last payment is 9/24, and I won't close till after then.
So it's something to keep in mind! If you purchase direct on current incentives but spread out payments, it will delay your closing and allow you to change to the new incentives if they are better!