Soundwave on 19 September 2014
Probably PS4. Nintendo really doesn't have any huge IP for Japan in 2015.
Zelda is not a big deal there, not anymore. Skyward Sword only sold 400k and it had a bigger userbase with the Wii. I think Mario Maker will actually outsell Zelda.
PS4 will have things like Metal Gear Solid V and Dragon Quest Heroes and maybe Final Fantasy XV. Uncharted IV will probably do OK there too.
Neither will have great sales though. I think you're looking at a baseline of 10-12k for the PS4 versus 6-8k/week for the Wii U with the PS4 getting a few extra bumps due to key game releases.
Vita will outsell both.
