We had no problems with Mosquitos on our Eastern Caribbean Cruise.
Sovereign of the Seas 2/03
Navigator of the Seas 2/04
Adventure of the Seas 2/05
Serenade of the Seas 2/06
Monarch of the Seas 7/06
Liberty of the Seas 8/07
Majesty of the Seas 5/08
I'm not sure if the is the same Linda from the other message boards, but I'll answer here just in case...
We like to vacation on St John (USVI) and stay at the ecotents (www.maho.org). Because we are outdoors a lot, we take repellant with a high concentration of DEET. This usually works for the noseeums as well, which you are more likely to encounter versus mosquitos (don't think we've encountered mosquitos). We also get a prescription strength cream from our doctor when going on land vacations "just in case" - we would hate to get eaten up one day and have the entire vacation miserable. I usually get the rx for Triamcinolone Acetonide 0.1% cream and have it filled prior to leaving home. The noseeums normally come out around the beaches in late afternoon and towards sunset.
We married on a beach on St John, but that was in the morning time, so none of our group experienced any intimate encounters with insects of any type.
At least on St John, we had no problem bringing repellant - even staying at the ecotents (which are very eco-friendly). We totally forgot to take any for our vacation on St Croix, but had no problems there at all.