The world's largest cruise ship, the Oasis of the Seas, set sail on its maiden voyage from Miami. At over 1,000 feet long and carrying 6,000 passengers, it is five times larger than the Titanic and has 17 decks. While some passengers enjoyed its many amenities, including a real-life park, critics said it looked like a large floating office building. The article discusses the massive size of the new cruise ship and mixed opinions about cruise vacations.