Probably not as powerful as the Iris Pro, after all it has no fan for cooling it so unless Intel have made something magical I would say along the lines of the Iris
I don't think anybody else used those chips yet. You will have to wait for benchmarks. I am guessing it will be 20% faster minimum or so based on simple math with memory speed and execution units. Question is the actual clock rates it will run under load. Chances are 14nm helps with the low clock rates and that will be whatever will be the percentage points on top of the min 20%.
Also, does anyone have any details on the new flash storage and RAM (I see it has a few more letters and mhz now)? I'm supreised PCIe based flash storage even gets any faster?
Probably not as powerful as the Iris Pro, after all it has no fan for cooling it so unless Intel have made something magical I would say along the lines of the Iris