1. The three displays WERE showing full black minimum MLL. I was actually there and can attest to this.
Do you really think that in a black level face-off, Panasonic are going to do as you describe and have their displays show grey instead of black?
It does seem like you have a vested interest in denying that, at the moment, it appears that Panasonic have managed to come up with a better AR filter. We won't know until we test a retail unit, but it certainly looks like they have.
2. People seriously have to stop assessing display performance based on photographs. It's crazy. You have variables on both the acquisition side and display side to consider:
1. PDP sub-field drive and how it interacts with a camera.
4. Lens aperture.
5. Any in-camera gamma (including any low-end crush done to hide noise).
6. Any tweaks done to get the image ready for the web.
7. Your own monitor (OLED or not, it doesn't mean it's accurate and it doesn't mean it tracks accurately out of black).
8. Your own video card / GPU.
9. Any OS-side settings (color profiles etc).
10. And more that I probably forgot.
Please read this and then read it again: these are for illustrative purposes only.
Sorry to be blunt or even rude, but it needs to be said.