I produced the following supplementary wiki page to go with the small PRD refresh. Because the PRD is not changing drastically, and was written with a fairly long horizon in mind, some work has been done, other work still remains. The Council report here adds a bit of detail, hopefully without going to the point of duplicating too much of our release points:
https://fedoraproject.org/wiki/Workstation/2015_report_to_Council
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