Congratulations to Joanna and Mark! Wow! We hope to get a chance to sail with Joanna again one of these days ... :D
Olivia - if you did it through iPhoto, odds are that the pictures are somewhere in your iPhoto library since it's highly unlikely that the program would have erased the photos unless they had been successfully copied. The only glitch with that is the memory card reader - if it had had some error, it is possible that it might have erased the card by accident (though pretty unlikely). If you really can't find the photos, maybe we should wait until you get back to Florida and then either Robert or I can iChat with you and take control of your screen so we can look for the photos. I'd do it now but given the bandwidth and the spotty connection onboard, it'd probably be hard to do it.
In the meantime, if you can spare the memory card that the pictures were on, you might want to reserve it and not use it for any further picture taking. One possibility is that the memory card itself is bad and it might do it again. The other possibility is that if the card remains intact, we might be able to retrieve the lost photos off the card itself if we needed to.