As Frank already pointed out, DX11 is not used in current games as those still need to support DirectX 9 for Xbox360.
Also I don´t see it as a reason against DirectX11, that it isn´t yet widely used in current games...
But if jcl decides to focus on other things in the near future, I can´t change that anyway, and I also am not sure if I want to, as he most probably has good reasons for his decisions.

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