While we got DirecTV for the 3D content when we were told we were a LiHD/Li3D family, we decided to keep Fios, since we're thrilled with the quality and the internet speed. So we pretty much do all our TV watching on Fios, and will occasionally switch to DirecTV to watch 3D content.
I was browsing through the On-Demand stuff on Fios and noticed they had a 3D episode of the Mercedes Benz Classic show, and today I tried to see if this would actually display in 3D on my Viera TV. I wasn't entirely sure since the Fios signal passes through the AVR, which is not 3D compatible. Amazingly enough, it worked like a charm, all I had to do was change the 3D setting on the Viera TV to Side-by-Side and the signal turned into a crystal-clear 3D picture!
Thanks once again, Panasonic, for being cutting edge!