FSX/P3D. This actually looks like yet another Aeroplane Heaven project but I can't find anything to indicate this. If not, then this is a new dev or an internal project. It's strikingly similar to the AH's Grumman F3F- 2 which is a really awesome addon. Either way, this is looking good so yeah, i'll get it when it's out.
ADX Update: Released! That Was Fast!