This is a feature that was introduced in Nexus Pro 1.3.2. You can use Nexus Pro in concert with the Nexus Maven plugin to manage the distribution of settings.xml files across your organization. When you setup Nexus, you usually have to convince all of your developers to install a custom settings.xml in ~/.m2/settings.xml to connect Maven to your repository manager. With this feature, developers can run a simple Maven goal which connects to Nexus Pro, downloads a settings.xml, and installs it into the proper directory. For more information, watch the video below. This feature is also documented in the Settings Chapter of the Nexus book.
Managing Maven Settings with Nexus Pro from Sonatype on Vimeo.