The next cruise will now be a 3 day cruise to nowhere beginning on Friday, July 2nd. Bording will begin at 2 pm.
According to the Carnival website, "Guests that sail on the new 3 day cruise will receive a 25% refund of their cruise fare along with a 25% discount on a future 3 to 5 day cruise departing prior to April 30, 2012 as well as a $25 per person on board credit as a reimbursement for the Cozumel government taxes and fees."
SOURCE: http://www.carnival.com/cms/faq/default.aspx#q-1