Email broadcast utility for MailChimp.
UPDATE: The latest release of RSVPMaker includes all this functionality and more, and has been updated to support version 3.0 of the MailChimp API.
ChimpBlast lets you compose broadcast email messages for use with the MailChimp service from within WordPress. You can compose messages in the WordPress rich text editor, import the content of posts, preview the results on your website, and then submit the resulting message to MailChimp using the API.
ChimpBlast was designed for use in combination with the RSVPMaker event management plugin. You can import your RSVPMaker events into ChimpBlast, add introductory text, and send out your event invitations. The RSVP Now link in the invitation will automatically be coded to include a reference to the recipient's email address, allowing RSVPMaker to retrieve that person's profile details so they don't have to be reentered manually.
You can import a your MailChimp template and add CSS to help your WordPress content display better, such as the markup for WordPress photos and captions, or your own stylings. The MailChimp service automatically inlines the CSS code to work better with email clients, which don't always respect CSS in the header.
Sign up for my mailing list at RSVPMaker.com and I'll be happy to send examples.