Analytics360 plugin allows you to pull Google Analytics and MailChimp data directly into your dashboard, so you can access robust analytics tools without leaving WordPress. You can visualize your site’s traffic trends and see how blog posts and email campaigns affect overall traffic. You can also isolate traffic coming directly to your site from email campaigns with the “campaign traffic” tab.

Check the growth of your mailing list over time. Compare new and existing subscribers. And if you’ve got multiple lists, see how they stack up to each other. Curious how all that new traffic ended up on your site? Wondering if more people are finding you through search or direct referrals? Analytics360 will break it all down for you with Google Analytics.

You can use the Analytics360 plugin without a MailChimp account, but users of MailChimp will see data about traffic sent to their blog via email campaigns aggregated with other stats.

Pricing: Free
Requirements: WordPress 2.7+
Source: http://wordpress.org/extend/plugins/analytics360/