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If we remove the Wii as something that caught lightning in a bottle for a few years with the craze of motion gaming/mini-game compilations, Nintendo's console performance has a fairly steady performance
NES - 65 million
SNES - 49 million
N64 - 33 million
GameCube 22 million
Wii U - On pace for under 15 million*
*based on where it's sales are at after 16 months on the market vs. the GCN/N64. Granted I think it will finish a bit higher than this, but not by much (20 million perhaps?).
Really is this much of surprise when looked at in a historical context?
The audience for people who want a console aimed more towards the tastes of a family/kids audience largely supported by Nintendo and not much in the way of good third party support has fairly predictable results for the last 15+ years and the trend has not been a favorable one.
The only way the Wii U was going to break this trend was if it broke through to non-gamers/fringe gamers like the original Wii did, but the tablet pad hasn't excited consumers in any where close to the same way and the appeal of Wii Sports/Fit has faded after several years, sequels, and me-too knock offs.
