That change came not so long time after they introduced projects since it was the first item in Geni that got under revision control, which means a long time ago. In the beginning only curators was allowed to start projects.
I am sure it was announced somewhere, but even curators seem to have missed it.
Followers can't see any more than what is listed in your public Activity tab.
You can control some of what create an event here: http://www.geni.com/account_settings/recent_activity/