tessellation is not a software feature, its a hardware feature, existed from 3xxx or 2xxx series amd cards (cant remember which nvidia series tessellation was a feature), they just used it very recently, its not because of direct x.. So basically Wii U is the first console that will use tessellation.
ok, yes... i was once again not being specific. while "tessellation" has been around for a very long time, it is MUCH more effective in the latest batch of high-end GPUs, which allow displacement mapping to work seemlessly with streamlined, instantly-scaleable tessellation processes when over a billion triangles are being rendered at any given second - the parallel units (and engine rasters) allowing for a much more dynamic programmable pipeline...
... and, while the tessellation itself is handled by hardware, it seems pretty misleading to me to say that APIs like Direct3D have NOTHING to do with its effective implementation (but that may not have been your point)...