Its a Matter of Economics
People just aren't making the disposable cash they used to. Layoffs, outsourcing, new credit card laws, high gas pump prices are all taking their toll.
Maybe a small portion of the public is becoming super rich, but for most people out there its getting harder and harder to drop half a grand on every latest game unit with a little bit better graphics and sound. Just look at the disappointing sales of the 'iPhone'.
Nintendo knew what they were doing. Sell something with a new twist and make it much more affordable for us peasant folk. IMHO they deserve the success they're having right now.