"We will phase out our free service. Existing free networks will have the opportunity to either convert to paying for premium services, or transition off of Ning. " not very hopefull
km4dev is using their own domainname and indeed no adds so this is not a free ning. But again what happens to ning is example why I am reluctant to use a hosted solution because you never know how and when they will change there policies. Therefore I still would like to mention Dgroups (completely working through email as well) and things as Elgg and Grabgrass, we do not need hosted solutions.