ITS AMAZING!!!! Okay, I got a little excited there, sorry
We're actually going in late August for the second time. First time we stayed in the Royal Towers, this time I think we're in the Coral Towers (I'm pretty sure those are the ones in the middle).
The food is VERY expensive...the whole place is pretty expensive. It's amazing though, be prepared to feel very pampered. Lots of stuff to do, amazing pools, theres practically a waterpark in the resort. We had a meal plan, which covered breakfast and dinner everyday. Lunch was usually just some fast food at sharkbites by the pool or some popcorn and a margarita
There is a dolphin encounter that you can get to by boat on another island. It's really expensive, but it was one of the most amazing things I have ever done in my life. They kiss you, dance with you, squirt water with you, hug you, swim with you....its great.
At the Atlantis they have so much to do...pedalboating, snorkeling, golf in the pool (seriously), plenty of activities for kids. They have a million places to eat, and shops (though they're Gucci, Versace...stuff like that). They have bananaboating and all those typical island activities on the beach that locals harass you to do. There is this thing called The Dig, which is a walkthrough aquarium, the "underwater city of Atlantis". It is themed beautifully, just like WDW. Scattered throughout the resort are other underwater tunnels and aquariums...we ran into them by accident.
I'm going to stop now, I can go on and on

If you ask specifics I'd be able to answer them better. BTW, I own Holiday In the Sun, and I LOVE that movie. Atlantis looks just like that.