Games Workshop does have long range plans, and often we are in the dark on these until they happen or at least get much much closer. After all the Hobbit films will someday be over, and does that leave room for a 4th or a new tabletop miniatures game from GW?
Please remember that these are rumors, and look very far ahead.
via Tim on Faeit 212
Looking far ahead, the Hobbit and the Lord of the Rings will be phased out.
Horus Heresy will be the third System after Fantasy & 40k and become the "Mature" Game for 40k.
There are plans for an "Mature" Fantasy game with Forgeworld Models too.
Both Games will become their own modified Rulebooks.