[Tamerlin]

Why does Apple need to be independent? How would be in Apple's best interests to take on the massive overhead of being a CPU manufacturer?

I'm not even convinced that it would be in Apple's best interests to be in the graphics hardware business either, but at least that doesn't entail owning a fab. Neither nVidia nor ATI fabricated their own chips, they contracted that work out to foundries like Chartered and UMC. Owning a fabless graphics hardware developer might work out for Apple, but I'm a bit skeptical about that. I'm also not convinced that it was a wise purchase for AMD though.