I’ll quote some of what we got from ESPC, and add the "so what’s this mean to me" text below each…
The new rule provisions address four topics: (1) an e-mail recipient cannot be required to pay a fee, provide information other than his or her e-mail address and opt-out preferences, or take any steps other than sending a reply e-mail message or visiting a single Internet Web page to opt out of receiving future e-mail from a sender;
MailChimp users, you’re okay. We include a one-click unsubscribe link that immediately removes people from your list if they want off. This reminds me. The other day, I got subscribed to a mailing list (a university alumni group) without my permission, then when I tried to unsub, it required a password. I had to create an account, get a password, then unsubscribe from their mailing list. Not only is that stupid, it’s going to be illegal.
(2) the definition of “sender” was modified to make it easier to determine which of multiple parties advertising in a single e-mail message is responsible for complying with the Act’s opt-out requirements;
If you send a campaign that is mostly an advertisement from a sponsor (let’s say you rent your lists) then who is legally required to comply with CAN-SPAM and honor unsub requests? You? Or the sponsor? I don’t know what they decided. But I hope the answer is "you and the sponsor, dammit."
(3) a “sender” of commercial e-mail can include an accurately-registered post office box or private mailbox established under United States Postal Service regulations to satisfy the Act’s requirement that a commercial e-mail display a “valid physical postal address”; and
This is a nice modification, because we’ve run into quite a few small businesses who only use P.O. boxes (such as from the UPS Store/Mailboxes Etc.).
(4) a definition of the term “person” was added to clarify that CAN-SPAM’s obligations are not limited to natural persons.
MailChimp users who are robots, alien life forms, or the living dead—you are now required to follow CAN-SPAM. Seriously, I’m guessing this would cover botnets and automatically generated email campaigns sent by your computer or something.
If you’re interested in this kind of stuff, and if you’re a major email sender, we highly recommend you join the ESPC. They cover legal issues like this (from each and every state, too) and they invite high profile ISPs and anti-spam company speakers for roundtable discussions all the time. We’re always learning what AOL or Goodmail or Yahoo or Cloudmark or Roadrunner or Microsoft or the FTC has planned just around the corner, so MailChimp customers can be prepared.