Recently Ning updated their Network. One of the changes is the creation of public profiles. These profiles were set up for all members. I didn't know these profiles were public until I read a post on another community.
If you have not seen your public profile, go to ning.com and sign in under your user name. You will find a list of your Ning communities, your Ning friends, names you use on your Ning sites and other info publicly displayed.
This can possibly be a security/privacy problem for some.