re: Big online genealogy includes things like ancestry, geni, familysearch etc, which are NOT wikis. Geni.com in fact uses Wiki software in their Project software. The controls are as tight or as loose as the project collaborators make it. Here's an example of a well controlled project with 5 active collaborators setting the parameters: https://www.geni.com/projects/RMS-Titanic/275 Geni's Basic membership is free, PRO membership gives access to more tools. Volunteer curators "look after" the "big tree;" about 200 of us world wide, with pockets of specialties. GEDCOM imports stopped in 2010.