Wow. NFC *finally* finds an actual use.
No doubt the "bolt on" nature will appeal to designers and mean designs can be moved between foundries a bite easier.
Obvious questions would be.
Do you feed the signal straight to the coil or is there some kind of protocol involved?
If so what's the overhead in bits per block of data (which could be 1 bit) being transferred?
What's the spacing limit between coils on the same chip to avoid interference?
And (perhaps the least checked of all) what's the maximum range that signal can go through? It should be a little over 1 chip thickness, but with 3D stacking I think some (all?) mfg's "thin" the chips to pack more in a standard package. So you could have vertical cross talk.
Yes it's clever.
But clever <> better.