Yes they do. As a matter of fact, every cruise I've been on has offered these meetings.
Mary Lou Scanlon
NCL Pride of America April 24, 2010
NCL Epic February 12, 2011
RCCL Allure of the Seas - September 18, 2011
Celebrity Eclipse - February 11, 2012:
RCCL Navigator OTS - February 9, 2013
All cruise ships have a designated time and space for "Friends of Bill W". I recommend attending the first day, when the largest number of people show up. It's easier to make contacts that way. Good luck!
On a cruise I took about a year ago, I had lunch one day with a woman who told me how she found out what "Friends of Bill W." meant, and how foolish she felt when she found out. Some time previously, she was on her third cruise in a row on which a "Friends of Bill W" meeting had been mentioned in the ship's daily program. She was astonished-- what an amazing coincidence that this same Bill W guy just happened to be having his family reunions or whatever on the very same cruises she was on! That guy must really get around!
Back on land, she recounted this astonishing coincidence to someone close to her-- I think it was her brother-in-law-- and he, being a recovering alchoholic and longtime AA member, just about fell out of his chair laughing. And believe me, we were all laughing at the table as she recounted this tale for our amusement.