I also believe that it is kind of PJ dipping his toe into the waters to test whether it is possible to have original stories set in the Tolkien universe which were not written by Tolkien.
The studio doesn't have the rights to the Middle Earth-verse, only to the Hobbit
books. After the third Hobbit
comes out, unless the suits decide to remake LotR
, and they won't, that'll be it, kaput. Hence the sudden serious interest in Warcraft