Joel Hruska: Historically, GaAs designs can't be used for p-type transistors very well. CMOS requires both. The hurdles between POET and your average smartphone or PC are enormous.

As long as Joel Hruska and others assume that the POET technology covers n-type transistors only and not also p-type, their stance is understandable, because – as Joel correctly states – CMOS requires both.

It strikes me that we here are so much ahead of the curve that we have discussed the ring oscillator under the aspects of speed and power consumption only. However, we lost sight of what is most important and should be most obvious:

The ring oscillator will first and foremost undeniably demonstrate that CMOS in gallium arsenide is possible!

The ring oscillator is a CMOS device and as such it requires both n-type and p-type transistors. If POET can deliver such a device, this fact alone will send seismic waves through the semiconductor expert communities. Text books and wikipedia articles about GaAs will have to be rewritten.

Big times ahead! Don't miss them, Hruskas and Klompens of the world!