Make pretty, people will buy
@John Halewood: Pixel size is way less than 4mm. Not done a precise calc but it's closer to 0.5mm.
I'm not a fanboi, my only Apple kit is a mk2 ipod that now lives in a drawer, but if Apple made this it would be 20mm thick with tapered edges, have a beautiful mix of glass and aluminium, and look like a piece of designer furniture. It would have a catchy name and a relentless advertising campaign to convince people that it was wonderful and that they needed one, and it would probably sell millions.
I've no doubt that MS could market it equally well if they really wanted to, they have sold 1 or 2 games consoles in their time, but sadly Joe Public has been somewhat brainwashed into believing that if Apple didn't do it/make it popular first then it can't be any good.