Oasis of the Seas sneaks out from behind some trees

The world's newest contender for biggest-ships-ever, the Oasis-class vessels will be a whopping 40 percent larger than the current title holders, Royal Caribbean's Freedom-class trio. Oasis of the Seas, the first of the two 225,282-ton, 5,400-passenger behemoths, is officially set to debut on December 5, 2009; sister ship Allure of the Seas will debut summer 2010.

Oasis of the Seas will be delivered from yard to line on October 28. The ship left for its second, and potentially final, sea trial on September 28. Following the sea trial, Oasis will undergo a final month of outfitting, before being turned over to Royal Caribbean. A series of pre-inaugural cruises will lead up to the November 30 christening in Fort Lauderdale, followed by the official maiden voyage on December 5.

The buzz surrounding these vessels has been unlike anything we've ever seen. Onboard zip-lining? A water-based outdoor theater? Loft-style cabins?

The layout itself is unique. The ship will be divided into seven neighborhoods, each with its own distinct theme. The seven: the Youth Zone, for the tots; the Boardwalk, with its Coney Island vibe; the Royal Promenade, a bigger, bolder version of Royal Caribbean's traditional indoor shopping mall; Entertainment Place, for the nighttime activities; Vitality at Sea Spa and Fitness Center; Pool and Sports Zone; and Central Park, an indoor/outdoor space with real grass and trees. Dining-wise, there are over 20 options. Twelve charge an additional fee.