AMD can become a serious contender if they decide to. AMD64 CPU's and Radeon GPU's on Radeon Motherboards could easily give any console a run for its money.
Intel for all its money would still have to license a decent GPU.
Apple's revenue model is more like Nintendo's, I doubt they will like to lose money and earn it via software. The Ipod h/w makes a lot of money and songs sold via iTunes barely cover their costs. Apple is basically operating iTunes as a service.
Heeeeyyyy!!!! <Snap>