Google Brings Ad Placements for the Google Mobile Ads Unity Pluginhttps://ads-developers.googleblog.com
Ad Placements is in Open Beta for app developers who use Unity. Ad Placements provide a cleaner and more intuitive way to place ad units from Google AdMob in your games. Ad Placements allow developers to add ad units with a Unity Editor interface, making the specification of ad units for your game centralized, re-usable, and decoupled from your scripts.
See the Ad Placement documentation for a download link to the early access build and instructions to help you get started.