Many associations find that their highly targeted, brilliantly crafted, permission-given e-mail marketing messages aren't making it to their members. Instead, they get stuck in the spam filters so many of us have come to rely on. Here's a tool from Lyris.com called the contentchecker, that may help. You can plug in your e-mail message and get a report on its likelihood of making it through the filter.
Of course, the spammers probably are using it, too, so I don't vouch for it, but it's worth a try.