The thing is, it will get harder and harder to sell home consoles there. So it all goes to when those japan titles are coming to PS4. Since PS4 is so focused on the west (and i am not saying it shouldn't), we could see really awful PS4 numbers there. You can't count with japanese third party yet, they are going to farm PS3 for the next years, unless Sony pays them to do different.
Saying it will overcome PS3 numbers is wishful thinking.
About Wii U, it does have some time to build some kind of advantage. All three versions of Hyrule Warriors now sits in Amazon's top 10, with the most expensive special edition sitting in 1st place! The second in the rank being Mario Kart 8. http://www.amazon.co.jp/gp/bestsellers/videogames/
Just saying, it could happen.
