This may be of use to those of you who maintain and support Thunderbird in your enterprise. The project appears to be open to community development, though.
http://www.zdnet.com/mozilla-scraps-thunderbird-development-email-client-not-a-priority-anymore-7000000469/
and from the mouth of the horse:
http://blog.lizardwrangler.com/2012/07/06/thunderbird-stability-and-community-innovation/
I hate to see this happen. Thunderbird was a great alternative mail/news client in Windows. Looks like they'll be doing ESR support like they do with "old" Firefox builds.
Since many manage Thunderbird in Patch Manager, I thought this would be of interest.
Thanks!
Jay