Pentax 645Z First Impressions Review on LL.
A very interesting read for sure. My conclusions:
For my purposes/uses I made the correct buying decisions with Leica M9, Nikon D800E, Olympus E-M5, E-M1, and Sony NEX-5N, -7, A7R. What's needed now is getting rid of some of the annoyances like shutter shock, LiveView not integrated into OVF, missing IBIS, ... .
The new Lytro needs an order of magnitude more rays at the same price. Then I certainly would bite.