Insted of hijacking an airliner these wannabe jihadi martyr's are training on self-propelled diving sleds. Kinda like the attacks on the USS Cole and the oil tanker Limburg, but underwater.
Reference the current issue of Soldier of Fortune magazine or Gordon Thomas reports found here:
http://www.trackingthethreat.com Al-Qaeda naval operations have targeted oil rigs, the brand new Queen Mary 2, the HMS Ark Royal, the USS Kitty Hawk and an assortment of large cruise ships departing from US and UK ports.
Personally, there is NO WAY I would be on board a cruise ship at this time. No Way!
By the way... WITHIN DAYS of the unidentified dead diver being found on Dania Beach, Hollywood, FLA, the USS John F. Kennedy pulled into Port Everglades with her escort surface combatant. I know, I was there. The overview of the area from the top of the Ft. Lauderdale Convention Center 6-story parking garage was outstanding.