Well, DTD is mostly a shopping/dining area these days. For the parents, it's a great thing, especially at night.
My favorite things at DTD:
Getting lost inside of World of Disney
Getting your free chocolate square at Ghirardelli
Checking out the soaps at the Basin
Checking out the combo of Team Mickey and TrendD
Pin trade or buy a few pins at the Pin Trading center
See the Art of
Disney store
For the kids, there's not as much to do, but there's a few things:
Disney Quest (expensive - but if you have it, it's good for spending several hours)
The
Lego Store - the kids get to play with the lego bins that are set out for them to use
There's a few little kid "attractions" like the train ride outside of the pintrading station
Spend some time in Once Upon A Toy
The rest is about dining and pure shopping. Also, at night, they usually have some performers on the stage in Marketplace and some other street performers here and there along the way. It's a good way to spend an evening if you have nothing else planned.