Numbers don't lie
Some stats
These statistics are not scientific since I don't have stats
from before I turned off greylisting.

Friday, August 21, 2009:
Spamassassin caught 180 message to me, my mom, dad, wife, m-i-l, f-i-l
Of those Spamassassin caught, 79 were to me.
Spamassassin did not catch 24 spam messages sent to me.
Of those, 22 were sent to OpenBSD mailing lists [*].

* The OpenBSD mailing list servers are whitelisted, so they would have
  gotten through.