With less than a week to go before first-quarter earnings, shares of Carnival (NYSE: CCL) got a boost this morning when German megabank Deutsche Bank announced a short-term upgrade to buy on the stock that it still considers a long-term hold. Carnival stock is full speed ahead on the news, its shares up 6.4% just after 10 a.m. ET. Rival cruise stocks Royal Caribbean Cruises (NYSE: RCL) and Norwegian Cruise Line (NYSE: NCLH) are steaming ahead in its wake, up 4.7% and 5.2%, respectively.