we just got back from a cruise.... it's awesome... several things to keep in mind....
it might be "all inclusive" but it's not really... you still get charged $10 a person per day for gratuity as well as all soda and booze are not covered... be prepared to shell out an additional 500 on top of your ticket costs.... (for gratuity, booze, and off shore excursions)
Also, make sure to get the patches that go behind your ears for sea sickness...
That being said, it's an awesome experience and we'll deffinately go on another in the future.