You can't just modify a devkit. I haven't checked for the PS4 yet (got a couple around me though), but on the PS3 the big devkits include extra memory that you only use during the early part of development to load extra things on memory and prevent crashes that you'd have to spend weeks and weeks to fix otherwise. The PS4 devkit is also bigger than a PS3 so I assume it includes a few extra bits and of course a bigger fan and whatnot, plus (I believe?) some recording system. But otherwise when you plug something into it, it runs the game like a normal console.
Using extra memory even just for some videos would be way too risky.... so no, I'd say this is how the game will look on PS4 (except better because Youtube blurs the hell out of it).