Hi Shannon,
The Mailchimp Form app is still available. It actually has more functionality than the original integration, and there is even more planned for it. It is built by a company called Mailmunch.
Some of the features:
-Sync All contacts, new and old (Original app did not do this)
-Has more information per contact (Original was FN, LN, Email)
-Comes with its own form builder
-Built-in analytics
-Forms can be customized, timed, etc
You can check out the app here . 