The Good: Pools, slides and beach are great. No doubt about it. Having a casino is a plus, but you can gamble in Vegas.
The Bad: Everything is expensive, from the rooms to the average food served throughout the resort. The rooms are nothing special. The service is absolute abysmal. They could truly care less if you are there and it shows.
Bottomline, take the same amount of money you are willing to spend on Atlantis and go get pampered and treated right in Hawaii.
Geat place. Lots of fun. very expensive. There will be lots of kids everywhere over New Years when school is out. With that being said, I have been twice and would go back. I would go to Hawaii like the above poster sadi if you have the extra time to travel.
I agree with the posters who recommend Hawaii; if Hawaii is an option, I would take it over the Bahamas.
Having said that, the wife and I had a great time at the Atlantis. The hotel is very nice and I really enjoyed the casino. It's probably the "nicest" casino I've been to outside of Vegas (keep an eye on the dealers though, they're not quite up to Vegas standards and will somtimes screw up your payout).