Quoting Damien Cassou (2012-09-13 17:15:30)
> On Thu, Sep 13, 2012 at 5:13 PM, Jeremy Nickurak
> <not-much@trk.nickurak.ca> wrote:
> > Gmail doesn't have folders, of course, it has labels, which are
> > approximately equivalent to notmuch tags. The key difference being that a
> > message can only be in one folder, but it can have multiple tags/labels.
> 
> Gmail exports its labels as IMAP folders: an email with multiple
> labels will be duplicated in multiple folders (one per label). That's
> why I'm asking if it would be possible to manupale folders from
> Notmuch instead of tags.

Daniel Kreischer contributed a feature to afew called mailmover that
allows one to specify a mapping between IMAP folders and notmuch tags
and move mails accordingly.

Justus