A $50 loss on each PS4 wouldn't do anything to Sony. Every buyer will give them it back and more within 6 months of owning the system through game sales and subscriptions to PS+, netflix etc. $100 loss and they'd likely be fine too. Once you get to around $200 then it becomes dangerous, because they could run out of money before they start seeing a return, but like I've pointed out before a $400 console that breaks even could trounce the Wii U in technical capabilities.

edit: in 2013, and easily in 2014.

I don't really think so, unless the Wii U ends up selling for $249-300.  Sorry, didn't get how this was related.  Also, a $50 loss on each PS4 probably wont do much if it sells every PS4, but you failed to mention that if the PS4 doesn't sell very much, it's $50 per PS4 PLUS how much it cost to produce each PS4 that is being lost, on top of many other things.

Funny, because the game that Sony has with the most diverse gameplay is Little Big Planet; which is a Sony exercise in attempting to make a Nintendo-like game.

If the PS4 doesn't sell much then they're screwed even if they make a $50 gain, because hardly any software will be sold and it probably won't make up for the R&D and other costs. Point is software is their main source of $, and software is not only the base games but now it's microtractions, PS+, app subscriptions (sony gets a share) skins/themes etc. and who knows what else next gen... So infact now they'll be even more inclined to take a loss on hardware because now there's even more ways to make it back through software.

Funny, because the game that Sony has with the most diverse gameplay is Little Big Planet; which is a Sony exercise in attempting to make a Nintendo-like game.

How much the Wii U sells for will be a bit reflective of how much it will cost to provide the system by the time it comes out

Just to clarify, here are you saying a higher price = probably better specs and vice versa? We already know the specs for the Wii U. Granted we don't know too much about the GPU, but it's rational to assume they'd be inline with it's RAM (1.5gb, though I've heard only 1gb is availiable to games I'll stick to 1.5gb) and CPU which is on-par or even sub-par to current gen consoles according to developers. Even if we assumed the GPU wasn't so far from durangorbis the CPU would still be a bit of a bottleneck and the RAM could be a huge bottleneck. 

 since they've pretty much said they'll be handling the Wii U like how they handled the price of the 3DS after the price cut.  So unless the Wii U sells between $249-300, then maybe selling at $400 will show a large enough difference in power if the other consoles release around 2013-2014 if they sell to "break even."  That's how it was related.

Also, selling at a $50 loss doesn't make the system THAT much more powerful.  A gpu that costs 100 and a gpu that costs 150 makes a world of difference, 4gb ram and 8gb ram is the same. But $50 is just adding to the cost. Let's say the Wii U is $300 (looking at the specs it's very unikely that it'll be higher than this and they will make a profit with this) at launch in 2012. Compare what you can do with $300 in 2012 (assuming they break even or a little less than that if they want to make profit on ahrdware out the gate) to $450 ($400 ps4) one year or a little more later. Big difference there, and that's with a relatively small loss on hardware, imagine Sony took a $100 loss? (which I think is more likely) or even $150? (less likely) That would surely blow the Wii U out of the water. I'm not arguing whether or not the PS4 will be more powerful than the Wii U since it's pretty much a given when Nintendo pretty much has made it their point that they aren't going for power while Sony's history would suggest they are more serious about providing power. However, in order to sell the PS4 cheap and provide a large enough gap between the PS4 and Wii U,  they will have to either wait a long time, or sell for more than just a $50 loss per system.