One of the reasons for upgrading is filling up a ship, reshuffling and so forth. The other (secondary reason) is that the happier you are, the more likely you are to book again, and consumer loyalty is what the cruise lines are striving for. So chances are, if you cruise enough and are flexible and early, and choose popular sailing dates, you will get an upgrade at least some of the time. Just don't start expecting it.

I think the best way to get upgraded is to book with a tavel agent who does alot of business with the line; and to book your choice of category under "gaurentee", which means you don't get to pick your specific stateroom, but you are gaurenteed to get at least what you paid for and at best an upgrade; and to be a past passenger of the line. I did all of this on a recent westbound transatlantic crosssing on the Queen Elizabeth 2 and ended up going from an outside, mid-range first class stateroom to a FABULOUS penthouse suite w/ a balcony and butler service, as well as a dining upgrade to the Queen's Grill Restaurant (the QE2 has different dining rooms for different classes). Having sailed Cunard before, I knew it was going to be exquisite (as it always is on Cunard), but this upgrade was certainly a pleasant surprise and a lovely bonus! I am sailing on QE 2 again in July 2000 for a 4 day R/T New York "party-cruise" and have booked the same way. My fingers are crossed, but I'm not anxious, as I know anywhere on the QE 2 is simply the best!