@Rol more tidbits here from Nintendo themselves.
http://www.nintendo.co.jp/ir/en/stock/meeting/130627qa/img/slide03_l.jpg
http://www.nintendo.co.jp/ir/en/stock/meeting/130627qa/img/slide04_l.jpg
http://images.nintendolife.com/news/2013/10/satoru_iwata_highlights_a_strengthening_worldwide_market_share_for_3ds/attachment/1/original.jpg
https://www.nintendo.co.jp/ir/en/library/events/130131/img/26l.jpg
http://www.nintendo.co.jp/ir/en/library/events/131031/img/09l.jpg
Most have Vita over Wii U in months/years for Europe and total. If Nintendo has more months of these charts that would be great. 2012-2014 Vita grew quite the lead.







