Number 1 on the list is "Critical to bring in more developers". This is very important, if you're interested in getting involved here, now is the time.
While my time for the very near future will not be that much, count me in for help. I will think about your list more thouroughly, but I see some areas where I can offer some immediate help, like point 3.12 (metadata) and 6.8 (WebDAV support).
I'll try to come up later with some more comments.
Ciao,
-- Gianugo Rabellino
