IGBT or FET based dimming has been around for quite a while. Unlike the posted schematic the circuit is usually realized by using 2 devices arranged in anti-series. The main reason to use this over conventional triac dimming is for capacitive loads such as electronic low-voltage lighting were reverse phase control is used versus standard phase control like you get with a triac. I have also seen this type of dimming in european dimmers that are "universal" in that they sense the load and can either operate in standard phase control for magnetic low-voltage lighting or reverse phase control for incandescent or electronic low-voltage. While IGBT's are certainly more ESD sensitive then a Triac more robust examples are out there.

Shawn