Player-made Geographic names are used quite a bit in the Maroccidens, I think. Heck, "Maroccidens" is one of the best examples of that.
Other examples include the Marwood, the Phantarian forest (known in Terran, at least), the Root River, and the Inner Sea.
Actually, Terran just renamed all three of its duchies to reflect the names they were more geographically associated with.
I much prefer player generated content, I just think there should be more of an effort to do so and use the names created. Even on Dwilight, but especially on the other continents.
