TUAW: A TUAW reader reports (with evidence) that if you use @me.com, @mac.com or @icloud.com services for your email, you could conceivably never see certain emails in your inbox. If you are getting mail from a “mail merge” service, like Constant Contact, Direct Mail, MaxBulk Mailer, MailChimpor Sailthru you might not see emails sent via those services or any similar product. It could conceivably be affecting services as well, but our tipster wasn’t able to test every one of them.
Note that the emails are not bounced, which would alert the sender, they are simply deleted entirely without notification to sender or receiver. Also, this only impacts HTML emails — plaintext emails seem to go through without a problem.