On Geni, the default is that all of the profiles you add in your family group are private. This causes huge problems for collaboration, since only family group members, not collaborators, can view, edit and merge private profiles. The best way to find new family members and collaborate is to make as many of your profiles public as possible.
One easy way to do this is by going to http://www.geni.com/list . On all unclaimed profiles, you should have the option on the right side of clicking "Make This Profile Public" to make them public. Alternatively, from every profile page you manage you can click Edit Profile and then in the upper right corner click the box for "This is a public profile".
When you keep your profiles private, you are only limiting yourself and the utility of the Geni program. You make it harder for people to find your tree, to see it, and to collaborate with you.
Is there some harm in making profiles public? Although many people suffer from a form of paranoid narcissistic disorder that makes them think that there are people out there watching their every move and looking for ways to harm them, the truth is that there are no documented cases of anyone using public information on Geni to harm any other person. So-called "identity theft" has nothing to do with genealogy, but is in reality a form of garden-variety theft or fraud (usually bulk theft of credit card numbers, but in some cases false applications for credit cards -- neither of which rely on genealogical information). There is really no measurable risk at all to making profiles public.
So please, make your profiles public so we can all collaborate and continue to build this great big tree on Geni.