If most people who use it leave it on the default setting of uploading pictures, etc. to Google+, and the right people start using it then more people will star

If most people who use it leave it on the default setting of uploading pictures, etc. to Google+, and the right people start using it then more people will start using G+ just to see their pictures. If those people start using G+ more then this could just be the killer app that kick-starts G+ to the mainstream.