ExactTarget released a whitepaper (pdf) to familiarize marketers with updated clauses to the CAN-SPAM Act.

The CAN-SPAM Act applies to commercial email and requires the following:

• That all email contain a clear, valid, opt-out mechanism. The opt-out cannot demand a password, or any other email beyond the person's email, to unsubscribe.
• Opt-outs must be honored within 30 days.
• Unsolicited emails must be clearly marked as advertisements.
• Sexually-oriented messages must be labeled with "SEXUALLY-EXPLICIT" in the subject line.
• No false, deceptive, or misleading email transmission information or subjects

The ExactTarget white paper includes best practices, and pitfalls to avoid, to ensure CAN-SPAM email marketing compliance.

A study found users increasingly mark unwanted email as "Spam," even if they originally opted to receive it.

Updates to the CAN-SPAM Act go live on July 7.