It's guided and the groups are smaller and more customized. For example, in promos they talk about that there's a water taxi to take you to the base of eiffel tower and they made reservations and try to skip the line when possible.
And they are familiar with the needs of families, and they interact with the kids and get the kids in the group to get along with everyone as the vacation goes along.
There are special behind the scenes access and exclusive oppourtunities in the vacations.
You get adventure guides.
And you get door to door service like luggage service and transportation and airport transfers etc...
They have taken care of a lot of the stuff that people don't always think about.
Instead of a fly by night random tour operator, this a tour offered by an established and reputable company, Disney!!
You stay in hotels that aren't disney, but disney takes you to see the sights on the tour.
So, for example, Disney takes you to see the Louvre. They'll have outlined activities for children. But if your children don't like the planned idea, the adventure guide figures out a way to try and get all the kids involved.
The idea behind this is that there a bunch of tour companies that will show you around at the grand canyon, but when doing it with Adventures by Disney, they do it better. They put together a hike, then a river raft, a jeep excursion, then a cowboy cookout...
And during these events, it's not a random dude with a rafting company who is possibly high on pot, it's a rafting company arranged by disney and appropriate for kids.
But there's no mickey mouse in costume in the promos. They do have some story telling by costumed people, but they might be dressed up as Ben Franklin or something appropriate to your itinerary.
Also, the tour usually includes a stay at several different places. So, when you are on the tour, they put together the reservations at each location so that you don't have to play travel agent.
You get a whole weeks vacation, and it's all as spectacular as going to the theme park. But instead of booking every single meal, excursion, hotel night, nightly entertainment, and all the transportation etc, you make one call to the travel agent and you book a pre-arranged itinerary with adventures by disney.
You don't have to do any driving. You don't have to spend hours putting together plans for every single day.
And there are extra perks you don't get if you tried to replicate the trip on your own. You get the adventure guides, and exclusive access (some line skipping, etc.)
This thread is a little old, but hopefully it's refreshed now.