I'm not sure I hold this suggestion in that high a regard. It's odd that some of the most highly intelligent people around enjoy consumption of 2 dimensional art forms - graphic novels, comics, xkcd. So I'm not entirely sure that I can see how 2D screens would affect their abilities... and honestly, I didn't even make it out of 1 dimension. Comics never really did it for me. I never really graduated from regular words on a page, maybe a couple of pictures or diagrams thrown in :P
That said, there are some great educational shows on TV that I don't mind them watching every waking moment if they decide they want to (How It's Made, Mythbusters etc.) It's the mindless rubbish (and the advertising!!) that seems to cast a spell on them that I object to.