You're comparing over 13 months of Wii U to 12 months of Vita, so you're actually still unfairly favoring the Wii U with that believe it or not.
13 months of Vita global - Vita Japan of the same month (which is 15 months) + Vita Japan of 13 months = 4.511 million in the same time.
And that's with one less holiday season than the Wii U in Europe, North America, and rest of the world. If you instead cut it to 12 months for both aligned, it's 4 million for Wii U and 4.4 million for Vita, so the Vita is actually ahead aside from Nintendo's great performances every Christmas.







