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

* XO Concentric easily exceeds any other ISP, sending 56 percent of invited e-mail to the junk/bulk folder; SBC Global and BellSouth are next, both junking 30 percent of permission-based e-mail; Yahoo! stands at 26 percent, followed by MSN Network, GMail and Hotmail, all at 18 percent;

* The rest of the top 10 includes People PC, USA and EarthLink;