Ok, few more thoughts.....
one of the letters sent to ICANN already mentions it, but nothing wrong in repeating.
So IMO the affiliate programs who opposed .xxx - some of them are listed at
http://www.fightthedotxxx.com/ - f.e LightSpeed Cash, Payserve etc ( and many many more ) - they should just notify their affiliates in a newsletter about this subject and instruct them how to protest.
If enough companies did it, it would significantly increase the number of webmasters who will protest. Especially since many webmasters don't read boards at all...