The "Wii is doomed" threads have existed since day one, often claiming the Wii's sales would disapear after it passed the Gamecube. All of these threads share the same underlying tone that people really want an XBox 360 or PS3 but are willing to tolerate a Wii because it is so much cheaper; for a small segment of the population this may be true, but in general it is incorrect.
If you look at the last generation and assume that there were 120 Million distinct console owners (factoring in multiple console owners, and people who had to replace consoles) then approximately 1/3 of these console owners represent the "Core" gamer demographic; this is the group of gamers who care about the "System Seller" games that are hyped, are willing to spend more than (about) $200 for a system, and are willing to buy more than one system. The remaining gamers represent many varied demographics who have differing motivations on why they buy a console but still share a couple of characteristics; on the whole they buy the most popular console (probably because it has the most games and because their friends own it), and they are unwilling to spend more than (about) $200 on a system.
Unless something dramatic changes in the market, the Wii will be the only system 2009 that is targeting the majority of gamers. If you look at organic growth in the industry (12.5%) as well as growth into new gamers (12.5%) the industry could grow to 150 Million distinct console owners, with 48 Million being the "core" gamer demographic, and 102 Million being the majority of console owners that will have very little reason to buy an XBox 360 or PS3 due to their smaller libraries, higher cost, and fewer friends who own these systems.
