Settings

You can find the settings for this plugin under Settings -> Discussion -> MailChimp Comment.

Plugin Settings

Mailchimp API Key

You can get an API Key on Mailchimp -> Account -> Extras -> API Keys.

See: http://eepurl.com/bt_Xqf

Username

Your Mailchimp username.

Server

You can find the server ID after the minus in your API key. It is something like us1, us2, ...

See: http://status.mailchimp.com/which_datacenter_am_i_using

List ID

The list ID is not the name of your list. You can get the ID on Mailchimp -> Lists -> [Select the list you want] -> Settings -> List name and defaults.

See: http://eepurl.com/bub8Jj

Checkbox Text

The text shown next to the checkbox under your comment form. You could use "I want to subscribe to the newsletter."