Lets call multiplatform games dominant (A) and exclusive games (a). Multiplatform games are dominant because they are the most cost effecient and most bought by the vast majority of people.
It would appear that most Wii owners of seventh gen are hybrid owners (a Wii and an HD console). Lets call Wii owners "Aa" because they own a Wii for exclusives and an HD console for multiplatform games.
A Wii U owner is homozygous reccessive because Wii U is built almost purely on exclusives. Wii U is "aa".
Because all the Wii owners of last gen are heterozygous (Aa), crossing them together would mean that approximately 25% of those Wii owners will jump to Wii U.
In a perfect world this would mean that there will be about 25 million Wii U owners when this generation is over with but that may not be the case.
A(squared) + 2Aa + a(squared) = 100% in a perfect world but this may not be the case. As the PC, PS4, and Xbox One continue to grab a huge audience potential Wii U owners may be swayed in a different direction. Poor leadership by Iwata and a 3DS version of Smash Bros will stop people from buying the Wii U. If Nintendo does not lose ANY of its fans I could see the Wii U capturing around 11% of marketshare. Because the Wii U is under poor leadership I could see it dropping further as the generation progresses. Any thoughts??
