Mack,
I'm sorry, but may I suggest that low hanging fruit has nothing to do with specific products but more server farm applications where power savings are immense and applications minor compared to very specific needs of certain product lines. PET seems to meet the needs of server farms directly while the full POET will be longer developing into consumer products.
However, I am still of the opinion that utilization by NASA/BAE/US military may be the first we see of market acceptance of our technology.