What we can see is that the Unity team is lot more people than A7 , that's why it's progressing so fast with support for iphone and Wii.
That might even be the most important and overlooked point. Even if some features are still msising, with a bigger team they will make it faster into the engine... or at least... should...
Their team isnīt only bigger, it also contains some of the best people in the industry.
