grep 'Esta newsletter foi enviada para' 2.html|grep -E -o "\b[a-zA-Z0-9.-._]+@[a-zA-Z0-9.-]+\.[a-zA-Z0-9.-]+\b"|sort -u|wc -l

este é melhor:
grep -o '[[:alnum:]+\.\_\-]*@[[:alnum:]+\.\_\-]*' Delivery_Status_Notification__Failure_.mbox | sort | uniq -i > emails.txt

para o phplist:
grep -o '[[:alnum:]+\.\_\-]*@[[:alnum:]+\.\_\-]*' Delivery_Status_Notification__Failure_.mbox | sort | uniq -i > emails.txt
cat emails.txt | grep -vE "@aefm|\.pt.|geadas@gmail.com|@mx.google.com|@lapxana-t440|@googlemail.com|Magalh@es|esc.fernao@gmail.com|\.google.com|\.hotmail.com|postmaster@|@moodle.aefm.pt|esc.fernao@mail.telepac.pt|gmail.com\.|otmail.com\.|mailinator.com\."> emails1.txt
cat emails1.txt |wc -l

http://www.putorius.net/2011/12/grep-all-email-addresses-from-text-file…
http://stackoverflow.com/questions/9377040/remove-duplicate-entries-usi…