We've recently launched Grouptivity for Movable Type 3, hoping to answer the needs of bloggers working with this popular platform. Movable Type removed the 'email to a friend' function some time ago, leaving MT users out in the cold, with no real way to forward the content to others.
The movable type plug-in does essentially what our other versions do: by simply
replacing the current 'e-mail this' link with Grouptivity EmailPlus link bloggers can enable content forwarding with the MT platform. The user analytics, are, again, invaluable since most bloggers are concerned with creating the type of content that attracts readers... well, Grouptivity's analytics allows bloggers to track the most read and forwarded content.
For information on our movable type plugin or to install the plug-in follow the installation instructions.