Visit this web site before it is no longer available:
http://www.bewareofgemcraft.com/ And visit HADD.com, Homeowners Against Deficient Dwellings, Headline News, September 17, 2007, to read how a new house owner is being sued by Gemcraft.
I took a quick look at the site and feel that a common mistake homeowners make on these sites is using the builder's logo. That may be the only legitimate reason they have given the builder to sue them, (providing the complaint itself is true). I believe trademark infringement was an element in the lawsuit Lennar filed against Mike Morgan of defective-homes.net which Lennar now controls.
Studying information on "gripe sites" and free speech may help homeowners make a site that is less risky. Anyone can be sued frivolously for their complaint site, but at least they should strive to make sure a frivolous lawsuit will have no legal leg to stand on, so the site has more chance of survival.