E-mail Marketing: Avoid Being Flagged as Spam; Update SPF Authentication

* Permission-based e-mails make it into U.S. ISP boxes roughly 75 percent of the time;

* AIM.com topped the list with 97 percent inbox delivery, 10 percentage points higher than second place Road Runner SoCal;

* The rest of the top 10 included (in order) Verizon, USA, CompuServe, iWon, AOL, Juno, Mac and NetZero;