This is a bit of history of the FreeBSD Developers wiki as remembered by SimonNielsen with the help of old mail archives to refresh memory.
The first version ran using the usemod wiki software but after a while the wiki started to be spammed with bogus content from bots. To fix this the wiki was switched to moinmoin, which is still in use as of this writing, and started to require authentication so only FreeBSD Committers could add/change content. The choice of moinmoin over other wiki software was made by Josef and as I remember it the choice was made since moinmoin was relatively widely used, supported the ACL's system we needed, and did not require a database back-end.
The switch to moinmoin happened 25 Dec 2004. At this time it also got the alias http://wikitest.FreeBSD.org. The reason of the "test" part of the name was to indicate it was not an official FreeBSD.org service as it was not yet certain how useful and used the wiki would be.
During 2005 Josef did not have time to maintain the wiki anymore so maintenance was taken over by SimonNielsen and the wiki was moved to run on a FreeBSD Security Team system hosted at Verio/NTT. The wiki started its life in a FreeBSD jail, so moving it was relatively painless as the entire jail directory could just be tar'ed up and moved.
2005 was also the first year of the Google SummerOfCode where the FreeBSD wiki was used of the students to write some of the information about their projects.
By August 2005 the wiki was physically moved to a server hosted by SimonNielsen as the Verio/NTT systems had to be reorganized.
In May 2006 the wiki software needed an overhaul as the install was becoming a bit of a mess, but with the help of FlorentThoumie (he did most of the work) the wiki was upgraded and a lot of the mess in the jail cleaned up.
On January 28 2007 the wiki was finally moved to sky.FreeBSD.org, an official FreeBSD.org system, so SimonNielsen wasn't single point of failure anymore (at least in theory) and the wiki got officially renamed to wiki.FreeBSD.org.
The wiki had been IPv4 only for a while since it ran in a jail which did not support IPv6, but on April 12, 2008 sky.FreeBSD.org had experimental patches from BjoernZeeb installed and the wiki got IPv6 support, though still not using the official DNS name. A bit more information about this can be found in SimonNielsen's blog.