[Users] IMAP server-side search?

[Jeremy Schneider]

Aside from reading source code and/or looking for patches... anyone
know where I can find info about the new "server-side IMAP search"
feature that was announced in the 3.9.0 release notes? For example...
when does it get used or not get used - do all the extended search
options support it?  Will any searches trigger downloading all the
message bodies in a folder?

Is there a wiki page or anything where this info is gathered? Since
this is something I'm using, is there someplace I could post a digest
of my findings if I ever manage to put that together? Maybe just back
to this list?  :)

Also, any quick tips about where to look for the actual source - I'm
curious how it was implemented and might read a little bit when I have
some time.

-Jeremy