I know there is a page here with some of the users here http://www.groupanizer.com/public-web-site-samples
I would like to suggest a simpler list of all choruses that have moved past the trial and made the decision to use Groupanizer with a link to their site. It could be a simple as a list with the names of the choruses licked to their sites:
Western Hospitality Singers Calgary AB Canada
Rhythm of the Rockies Calgary AB Canada
Bay Area Showcase Chorus Santa Clara CA USA
and so on...
For current users it would be nice to see what other people are doing with Groupanizer.
For potential users it might help promote Groupanizer if they see how many choruses are using it and the wide variety of sites that can be built with it.