I worked with the developers of yuku.com from May 2005 to November 2008. At the time, Yuku was a hosted community software setup which was being built to continue on where ezboard.com left off. At that time it was owned by Kickapps.
My involvement with yuku was a mixture of speccing how features should work, and assisting with the build of html and css in the core product. One example area in which I was largely involved was the member management feature within the community management area.
I also created a number of “skins” for users of the system to select when setting up their communities or profiles. Many of these skins are still used in the new social networking system that they have created since I left.