Great post !! We need to have a rep system in kikizo . Anyways , i feel the casual gaming thing is here to stay . As nintendo has proved , that crowd is more lucrative than the ' hardcore' crowd .. They wont buy many games but the hardware will surely sell .
Remember though, it is only lucrative to sell them hardware if you are making a profit, like Nintendo has since the release of the Wii, or like Sony has with the ps2 later in its life cycle. MS lost tons of money selling its Xbox for cheaper than it was to produce, same to a lesser extent for the 360. We all know Sony' s ps3 is costing them too.
Now, in a couple years, when MS and Sony start to make money off of console sales, then it will be very profitable to have casual gamers buying your console, and not surprisingly, that is around the same time casual gamers do start buying the consoles for a number of reasons. The foremost being, low price, and a wealth of both casual, and hardcore games.
Nintendo' s strategy of selling lots of consoles, and not many games(in North America, not talking about the DS attach rate in Japan) works well for them, but applied to Sony and MS, it wouldn' t be nearly as lucrative.
MS cleary has the most lucrative audience out there, with high attach rates of games and peripherals, but at the same time, it isn' t the largest audience. Casual gamers will always be bigger.