After reading all these stories, I was fearing I would need to go out and buy a BluRay burner just to watch some of the samples and videos available on the net. Tried calling Panasonics' Tech Support and they couldn't even tell me the type of formatting a USB needed (only supports FAT32, not NTFS)! Of course they had no clue what I was talking about when I asked them about the video formats supported... All they could say was that they supported most video formats generated by Panasonic video recorders, and that they didn't not support common formats like mp4, avi, mov, or mkv... in this time and age... unbelievable!
At any rate, via trial and error, here's what worked for me in case it helps others:
1) Obtain a copy of a side-by-side 3D video (don't worry about formats yet)
2) Use a video converter program (I use Xilisoft Video Converter Ultimate)
3) Based on Panasonic's manual, I tried all the AVCHD and H.264 formats but they weren't recognized by the TV or Blu-ray Player
4) Finally, converted the video into "HD-Xvid Video" (Xvid HD Video Format) which generated a .AVI file
5) Copied the file to a USB, plugged it into the Blu-ray Player and clicked Play
6) It showed the side-by-side video, so on the TV, chose Viera tools, 3D, and switched from Auto to Side-By-Side
7) Voila! Put your glasses on and enjoy!
TIP: Depending on the size of your 3D video, it is very likely you'll exceed the 4Gb limitation of the FAT32 format. So as part of the video conversion, you can split the video. I opted for ~4Gb segments which you can easily copy to the USB or burn to a regular DVD (Blank Blu-rays are still expensive...)