So I googled 360 degree videos. en.wikipedia.org/wiki/360-degree_video So there's a format but you need a decoder somewhere to allow the viewer to mouse around and for the relevant section of the fisheye image to be rectified. Where's that decoder located? Is it in our computers and the decoding happens after we receive the full file or does our mouse drag signal fly through the www to Vimeo who then just gives us what we need? Pretty impressive.
Gopro 360 on backy mount from k4 fins. It took me a bit of trial and error on how to get it into a format that works for vimeo.
There is something called spatial media metadata injector that takes the 4k flat video (4096x2048) and makes it rotatable. When I watch the 360 footage in the gopro player you can actually zoom in and out as well as pan left/right/up/down, which is very cool, but I don't know if that is an option for vimeo.
Most of the time I just render the 360 footage into regular 2D footage.