Yeah, I hate games that runs at 50 fps and has flickering when a character gets hit. Then when it's converted to 25fps on YT, the flickering effect turns to invisibilty cuz it usually cuts away the frames where the character is showing.
This is ofc only a problem with YT due to their low framerate. People should download our movies instead :P
But it's to my understanding that with the HD option, it KEEPS the original movie's fps.
I have upped a 40fps movie that runs fluidly on YT. With 40fps as original converted to 25fps should give noticable hickups in the framerate/motion, but it's not. So I think it keeps the original fps for HD movies at least, or mine would be choppy, and it's not.