Deja Vu and Jamais Vu
As you may have heard, both Sony (PS3, PS4) and Microsoft (Xbox 360, Xbox One) have their own piece of exclusive content for Metal Gear Solid V: Ground Zeroes. This isn't a pre-order bonus mind you -- it's built into every copy of the game.
Naturally this can lead to a choice between the two, so let's take a look at what you're getting.
Deja Vu (PS3 and PS4):
Before you get excited -- no, Deja Vu is not a mission starring the 32-bit version of Snake (at least, until you unlock the first costume) -- you'll be playing as the regular old Big Boss model from the main game. In fact, it's not even a "serious" mission, as your task is to "recreate" scenes from the original Metal Gear Solid by way of a photo shoot. It's a "historical re-creation" that takes place in the same location as the core game.
Sadly, the actual task is poorly implemented. Guards are still patrolling the base, and if they spot you, you'll have to take them out or hide like always. It would have been great if they went all out with Deja Vu and basically made the base like a special museum without guards (and a full-blown 32-bit veneer), but that's not what happened.
Alas, you're going to go on a scavenger hunt to find different scenes that are set up kind of like Solid, at which point a screen will flash, showing the old event for a few seconds. There are a few wacky things like an Easter Island statue and an "encounter" with an apparition of Psycho Mantis, but these aren't much more than a few fleeting seconds, with references from the original peppered in. There is a surprise for dedicated fans at the end though, and two fanservice oriented costumes (one of which can dash quickly like Raiden in the other DLC) can be earned that are only usable within Deja Vu.
Deja Vu is definitely worth playing once, but more effort on the part of Kojima Productions would have been great -- I'm not sure I'd ever play it again.
Jamais Vu (Xbox 360 and Xbox One):
Thankfully, the Microsoft-exclusive mission is a little better. This one features Raiden (albeit without a functional sword), who controls a bit differently than Big Boss -- mostly due to the fact that he can run super fast, with little lightning bolts trailing his feet.
He also gets a really cool reveal (introduced by Kaz Miller as a "war machine from the future" as he slams into the ground, jumping from the chopper), and the entire presentation is much better than Deja Vu, as the XOF badges are actually built into the intro. This is all taking place while a song from the Revengeance soundtrack blares in the background -- pretty badass.
Jamais Vu is also more interesting on a macro level, since the entire premise is built on snuffing out Body Snatchers, mysteries entities that steal the bodies of humans -- a direct reference to Hideo Kojima's Snatcher. They operate just like regular soldiers, but they burst into green flames upon death and get right back up after being tranquilized, which is a nice effect. There are also a lot of little touches like the ability to make Raiden speak (briefly) while interrogating enemies that make this a much better effort overall.
The mission is still stealth oriented, and there's even a reward for no alerts -- but you can go in guns blazing all the same, so it's fun to play multiple times over. It's also enjoyable to run around the base at high speed with Raiden if you're prone to messing around.
Which version should you get?
In terms of visuals, the PS4's 1080p is noticeably better than the 720p maximum from the Xbox One. You'll notice it especially when it comes to the rain effects and other small nuances that all around look better on the PS4. It's not like the Xbox One version looks poor though, and it does have the better exclusive mission.
Basically, if you love Raiden and don't care about graphical differences, just get it on the 360 or the Xbox One. Otherwise, stick with the PS4.