SJ - it's hard to say, but any that get wave action (more than a little) are usually lost. So that would mainly be the ones south of 30-A and definitely the ones closer to the inlets. As I'm sure you know it's the walkovers, seawalls, and now decks and homes that are the majority of the debris.
Some of the walkovers that were built after Ivan were much bigger (better right?) than the ones that were on the same spots before, adding to the volume of wave-strewn lumber. It will be interesting to see if people scale back this time for monetary and practical reasons. Who needs pavillions, gazebos, benches and BBQ areas on a walkover? Those same houses already have yards and decks for leisure activities. Or at least they did.