In fact DO exist, developped by Lookheed Martin under the name of "Prepar3d"
(And since 2010...)
Multicore, AMD / eyefinity gold cert, retro compatible scenery with FSX.
http://en.wikipedia.org/wiki/Lockheed_Martin_Prepar3D
http://www.prepar3d.com/product-overview/
Happened a bit the same thing as with Sonalyst Sub Command simulator, start as a game then go pro/semi pro.