This release of the MailChimp extension fixes two bugs in the plugin that may or may not affect you, depending on your plugin configuration.
First, it corrects a bug when using WP-Members moderated registration (where users need to be approved by an admin). The bug is that if a user does not check the subscribe checkbox, they are still added to the list when they are activated. This is now fixed.
Second, if you have more than 10 list (audience) IDs AND the list ID being used for the plugin is older, so that it appears at position 11 or later, you may potentially receive an invalid list ID error message when trying to update the plugin. This update changes the way the list ID is validated through the API to correct that problem.