»How to Advertise Responsibly Using E-Mail and Newsgroups or – how NOT to $$$$$ MAKE ENEMIES FAST! $$$$$
»Help for Marketers from Fight Spam on the Internet!
»This in particular is really on the mark:
Bulk email can be a powerful advertising medium. However it can also kill your reputation and get your web site shut down. If you advertise through bulk email, please be very careful about who you use. As an advertiser, you share in the responsibility for how email is sent. If you support a spammer with your advertising revenue, you share the blame for the spam. It is your responsibility to verify the management of the lists you support.
On the other hand, even the most well-run list may generate some false spam complaints. You should talk to your internet providers before you begin any bulk mail campaign. A list is judged not only by how many complaints they generate, but also on how they handle those complaints. – from Help for spam report recipients on Spamcop