This is from the Atlantis website:
Do I have to have a great body to fit in on Atlantis?
Very funny. Seriously, while we have some great bodies in our brochure and website (remember it IS marketing after all), Atlantis is really all about being yourself and feeling great about who you are. Whatever shape you’re in, you’re going to feel right at home on Atlantis. We promise.
Here is an article about "Is an all-gay cruise for you?":
http://www.cruisemates.com/articles/gayles/Atlantis.cfm
They say: "We met many nice people on the Atlantis cruises that we took. Not everyone on these ships is the buff circuit-boy type like you see in some of the brochures. There are lots of ordinary, everyday people -- from different age groups, with different builds, and from different countries."