If you click on the little bell on the top right of your Constant Contact account you'll reach What's New in Constant Contact. Currently, that's the January release notes.
I find these release notes useful - they share the latest editor improvements and other fancy stuff. My favorite change recently has been the ability to instantly add someone to a new list depending on what link they click - ie, segmentation.
This is an improvement that keeps growing on me. Let's say a person clicked on the link featured above - that could lead to a new autoresponder email (or series) coming their way. I keep finding new ways to use this -give me a shoutif you'd like to discuss this further.