...and save them to an SD card or send them through the internet? Basically reading the screens and doing stuff with that data, or do we need IOSU for that?
It is more possible than the 3DS. People said we'd never get video output on that, but we already have 45+ FPS in most games. With an IOSU exploit, it should be possible, But capture cards are cheap nowadays so people probably wont have interest in this.
60FPS HDMI ones aren't, unfortunately. This is something I've been interested in from the early days of Wii U homebrew
I got a 1080p one that records at 30FPS for $30 (USD). I had test videos on youtube but deleted them because of copyright infringements. I might do another one later.
The Wii U is a weak machine and cannot just send the HD video and be fine while running the game. It will lag behind and never catch up to the current state. Just buy a capture card if you really care about recording anything in a "proper" way (not using a camera).
For that price, it's generic, but I hardly think that matters as long as it records in good quality and works.
