The mail-to-blogger feature of BloggerPro has been completely reworked and all users should notice a signifcant increase in reliability. Specifically, the mail-to-blog address can be put in the bcc: field of your email, ensuring that your secret mail-to-blog email address remains secret. Also, emails can be formatted as plain text, html or multi-part which will resolve problems users were having with email sent from Exchange.
Please note that <pre> tags should not be used in html-formatted email and <body> tags should not contain parameters. If you're experiencing other problems, please create a BloggerPro issue in Control.
Thanks to Misha for rewriting this important feature and to Rudy for setting-up and administering our new mail server.