Bump noted.
https://www.youtube.com/watch?v=7TJ7IUNWGl4&t=4m38s
First live footage of the Switch in the Tonight Show with Jimmy Fallon (second half of video), featuring BoTW.
It appears that the fps is quite smooth on the Switch handheld (within the limits of streaming video ofc) when not docked, though of course we can't tell if more intense environs would result in framerate drops. I don't recall if we've seen the armor and shield Link has in previous demo videos or playable demos.