I have never been to the spring
Annapolis show. I've been to the last 10 fall shows. Mostly new boats, and as others have pointed out, the manufacturers will post on line their models that they are showing. Of course, that is subject to change a bit as many manufacturers "rent" a particular model from a customer, as they may not have a model in hand or the distance to move one is not as cost effective. Things happen and sometimes boats fall out at the last minute, so look at the websites in mid-September and you'll get a good idea. Also, catamarans have become more numerous over the years. Don't know if they out number monos, as I have not done a count, but since they take more space, they seem almost ubiquitous.
Across the highway crossing Spa Creek is the display area for used boats. Those are whatever the brokers feel will sell best, obviously, and ones they have permission to move. It is a short walk (5 minutes) from the main display area. There are far fewer boats here, as the show has featured new models. I cannot
recall if the models on display were listed as I did not get to that exhibit--I was mostly looking at
gear. Perhaps looking at the website will tell.