I think webmasters (adult and mainstream) need to step back and look at the Flash abuses going on right now. At this point Flash is primarily used for cartoons, games and annoying advertisements. This means that the average web surfer may see fit in the near future to block Flash.

Webmasters abused popup's and look what happened. Flash is next. This is going to be a big issue within 2 years. Mark my words.

As for the adult industry.... I think sponsors almost have to pull out all the bells and whistles to attract the average affiliate these days. Some of the best converting paysites out there have a bad sponsor page backing them and affiliates simply won't touch the program. Yet so many other sponsors have spent more on their sponsor page than on any of their paysite tours, and they get the affiliates. And many times, Flash comes into play.

For paysites, I'd never implement Flash in a way in which usability of the site was dependant upon it. Especially considering some Flash is processor dependant, and it just looks bad unless the user has a faster computer.