I miss the old days when Preview Night was exciting as Hell. As a non-attendee, it was still a lot of fun. Now everything is pretty much previewed before the show, so it's not as exciting once the pictures roll in.
You do see some of what's going to be there but for me its still as exciting as ever. Getting a chance to see all this in person still is goosebump inducing. I will say also know what's going to be there helps me know what I want to take pictures of first.