The International Internet Genealogical Society (IIGS™) is for all genealogists. We have the technology and the medium to jointly manage and run it. We are all leaders; we are all followers.
All the really large internet projects have no management at all. *None* You cannot find any one person in charge of Linux development, or Usenet news distribution, or packet routing - all fundamental to the workings of the Internet. Thousands of people do not wait for instructions, they just do whatever it is they feel needs to be done. On the other hand, projects tend to become very disorganized and corrupted every time someone tries to impose a hierarchy.
It is not a surprising phenomenon that success can be achieved without a formal hierarchy when you realize that the flow of information is near perfect on the net (lousy communications is one of the reasons there are hierarchies in the real world), and there is no way to coerce others to behave in any particular way on the net (hierarchies are fundamentally dependent upon the ability to coerce subordinates to behave according to the dictates of folks higher up). Think like an experienced internet user. This means giving up on the expectation that you can ever hope to tell another netizen what to do. You do your own thing. You do what you can to enable other folks to do their own thing. Then you try to roughly herd all the cats by sharing information and helping others to build a common vision.
Do not worry too much about things going a million ways at once. That always happens at the start of a new project, and after a bit, the folks that hang in there tend to self-organize into something that starts to make sense. After a while you sort of learn to love the million-directions phase of a project. A lot of energy gets wasted, but you learn what works and what does not work a lot faster than if you carefully plan and then learn about all the things you did not know by watching your plan get broken a dozen ways.
This is fun, make it fun, have fun!