Earlier this month, Quim Gil and I gave a talk at FOSDEM:
Wikimedia adopts Phabricator, deprecates seven infrastructure tools:
First hand experiences from a big free software project on a complex migration
The talk description and the presentation slides are available. At some point there will likely also be a video (probably under 2015 and H1308).
The talk tried to cover three aspects: The decision driving process in a large distributed project, the technical and planning aspects of such a complex migration that nobody has tried before, and describing some of the functionality of the new tool (Phabricator) itself.
