The ever-resourceful Andreas threw me the following email just now that I found notable, especially as a Gmail fan. Bless him and all the dudes who do these types of seemingly pointless yet ultimately informative tests for us.
I just went back through my gmail archive to train it on some spam that leaked through. I do pretty well in the email fight:
since march 26, 1000 messages have been delivered to my desktop (ie made it through the spam filter). of those messages, all but 14 were legitimate.
additionally, I receive on average 25-50 msgs/day that are caught by the gmail filter. that’s roughly 1000+ pieces of spam over the same time period. (so 50% of the email sent to me is spam! and I bet that’s below average.)
so 14 out of about 1000+ total spams got through. that’s almost a 99% success rate for the gmail spam filter. that seems pretty good to me. and outlook’s junk filter catches the rest, so really 0 spams make it to my inbox.
on the flipside, I do still get about 1 to 2 false positives per month that I have to rescue from the gmail spam folder. but I bet if I had my addresses uploaded to gmail and/or used their smtp server to send out, it would learn better who’s on my whitelist and those false positives would disappear.