heyho.
in the documentation it said, bbdb would work really well with message 
mode. my problem now is, that it is stated nowhere how to feed the 
database of notmuch to the bbdb initially.
is there a way to export all the mail addresses in the maildirs to 
plaintext files?
bbdb-snarf gives a pretty good address scraper for plaintext files or 
emacs buffers, but as far as I could see it there is no way to just show 
all the senders' addresses.

does anyone know how to solve this discrepancy?

apart from that, notmuch might be just the right solution for me.

best,
dan