We had the same thing, mixed but mostly positive reactions from his friends and family, but mine were negative.
We let eveyone know almost 12 months ago that we were having a destination wedding, and gave them 22 months notice with the save the dates.
I think its one of the big things you have to decide before you choose a destination wedding - that if it ends up just being the two of you on a beach getting married - then thats OK. That was our starting point, so anything from there is a bonus.
I know that there will be people that are dissapointed becasue they can't /won't come, but at the end of the day, the wedding is not for them!