We used the DDP for the first time in August. The main reason was that, during our '06 trip, DH was pretty cranky paying those prices for meals, especially when the kids didn't eat it all OR fell asleep at the table

. Paying for it all upfront removed that particular souce of trip-stress. We did eat at some restaurants we might not otherwise have tried, and for the most part enjoyed that. The 2 big drawbacks for us were:
1.) DD#2 is 5 years old, so she had to order from the children's menu. She can only eat so much mac and cheese or chicken nuggets before she rebels, and I don't blame her. The children's menu is WAY too limited for a 7 night trip.
2.) This one is my own darned fault, and I know that. Because the DDP costs so much, I was determined to get as much bang for our buck as possible. This meant dinner TS meals since they typically are more expensive than breakfasts or lunches. The problem for us was mentioned already in this thread....it was tough to be having a great time at the pool and have to haul everyone out to get ready for a dinner ADR. If I had it to do over again, I would book lunch ADRs at that day's park and save the CS meals for dinner. We tend to leave the parks by lunchtime anyway, so having a nice meal on the way out, then heading back to the pool would work better for us.
All of that said, we're not buying the DDP for our next trip. I think it's a total ripoff that they removed the gratuity, and the kid's menu just doesn't cut it for DD#2. The kids really don't give 2 hoots about where we eat, anyway. Both times they were given the choice of ANYWHERE in WDW to eat last trip, they chose the POR food court.....and we weren't even staying at POR

. We'll do a couple of sitdown meals but most of our meals will be CS.