I can say from our experience of about 50+ communities, suggests there is NO one answer. I am almost ashamed as a consultant to report that I cannot detect a consistent pattern. Alternatively any of the tactics adopted has different outcomes and some of these outcomes could not have been planned at all before. E.g. One of our customers as I mentioned initiated a purge process for a subset of the 90% to get their ad sponsors all upset and wanting reduced prices.

What I am seeing is within the types of communities there are patterns. Just too early for me to tell whethere the patterns are transient or permanent.