Some recent dissection of the news on both ends, courtesy of Slate.
Links to Karl Rove are present for the Swiftees, and disseminates what can and can't be back up (nothing apparently) by the group criticizing Kerry:
Swift Vets Deceptive
A similar issue - non factual information and unsubstantiated claims by Bush basher were quashed really quickly in 1999. The same can't be said for the Swiftees, who have gotten a lot of play.
Account of 1999 Bush book that got wiped out.