Whitelist spam filters are probably the last hope for dealing with spam in a meaningful way, and I can tell that people are starting to use them — the last notification email I sent out resulted in a few replies saying “please respond to this message with blahblah in the subject line if you want me to read it” which is what the whitelist programs bounce back.
I can’t really process all of these bounces manually; my mailing lists are managed by a professional service provider (Whatcounts; recommended). The moral of the story is that if you have a whitelist filter, please make sure that *@whatcounts.com is allowed or you won’t get the mailing list. Also, all mailing list messages will always contain [JoelOnSoftware] in the subject line.
Open Source and Usability
Matthew Thomas, a Mozilla contributor, wrote something interesting about why free software usability tends to suck.
Coupons are Fun
(The serious point of coupons is that they let you try different offers on different people and figure out which ones are the most profitable. For example we could send 1000 people a coupon for $20 off, and 1000 people a coupon for $40 off, and compare the response rates).