I think that if I were researching a cruise, and it came down to this cruise or that, a guest speaker could make a difference.
Sorry Hugh (and he lives here in my home town), but I'm not so sure you would be the one who would do it for me. But take Silversea's Egypt cruise booking the leading Egyptologist in the world, the same guy who hosts all the shows on the Discovery channel and discovered the most recent tomb. THAT kind of a speaker would do it for me.
I have been on music cruises that were a BLAST! By the way - but maybe the question is this..
WHO WOULD BE A STRONG ENOUGH PERSONALITY THAT YOU WOULD BOOK A CRUISE JUST TO BE ON THE SAME SHIP WITH THEM?
John Lennon, [Jesus, Mohammed, Moses, Buddha], George Bush, Hillary Clinton, Al Sharpton, Sean McHannity, Don Imus, Howard Stern, Tom Cruise, Paris Hilton, Princess Diana (assuming she were still with us - not in the condition she is now), Prince Henry, Mao Tse Tung, Jerry Falwell.
Is there anyone who would make you book a cruise to see them?