As of Xenforo 1.2, tagging users is a part of XenForo built-in functionalities and this add-on adds the following features:
1. Tagging in profile posts, profile post comments.
2. Tag many users at once with @user_group syntax.
3. Tagged users will receive alerts and emails (user configurable)
*. This version of the add-on DOES NOT support XenForo 1.1.* and below.
1. Upload files/directories under `upload` to your XenForo's root
2. Import add-on xml
3. Start tagging!
4. Configure user group permission: "[Tag Me] Tag group"