Every company has happy customers; why not engage them? Look through your mail and identify your most enthusiastic customers. In addition to thanking them for their kind words you should also tell them about discussion groups and web logs who follow the industry.
Dear Mr. Happy Customer:
Thank you for your kind words about TheLittleEngineThatCould’s new WidgetWare software system. I have shared your letter with our development team who appreciate your feedback. We will also take into account your suggestions in the next release of WidgetWare.
In view of your interest in the industry you might be interested in following the Yahoo discussion group [ULR] and these popular industry blogs:
Then sit back and let nature take its course. If you routinely notify your happy customers of discussion groups and blogs which follow the industry, it is only a question of time before some of them mention your product in a favorable light.