DEC 16
This “R2” moniker has gained favor in Redmond in the last few years as a way of saying, “It’s the same software, honest! We’ve nailed on some bits to the side.” It’s supposed to appeal to IT departments that are allergic to disruptive changes.
It goes both ways; versioning and product descriptions are definitely influenced by marketing depending on what’s wanted. A big update seems a lot safer when served as an incremental bump in the product, and a small update can look more impressive by revving the actual version number.