I've spent quite a bit of time last week on this document: https://fedoraproject.org/wiki/Workstation/Technical_Specification
It is not 100% complete, but I haven't found the time to get back to it since Friday, so I should probably open it up for a first round of review to the other WG member.
Let me know what you think,
Matthias
desktop@lists.fedoraproject.org