Ok, here's what's really happened.
The issue is heat and power. Apple has spent the last year or two trying to get an Intel Core Duo to run cool enough in the confined spaces within the new iBook/Macbook case. And it's just not working. Intel have promised they're going to produce more power efficient Core Duos, but so far they're having trouble doing this.
So, they're looking at a number of options. And here's the deal: the most probable outcome is that at this coming WWDC, Steve Jobs will stand up, and tell the faithful that with immediate effect, the entire Mac line is going to transition to ARM.
This may seem drastic, but it'll ensure the next generation of Macs can be smaller than ever before.
But this isn't the end of the matter. New ARM based Macbooks will be ready in time for MacWorld in January. However, while powerful for Macbooks, Apple is going to have difficulty getting chips that are both powerful and power-efficient for the next line of StrongARMMacs. So, in WWDC 2007, Jobs has been preparing for a major, shocking, announcement: The entire Mac line is going to transition to SPARC.
This may seem even more drastic, but it'll ensure the generation of Macs after the next generation will be smaller, and more powerful, than ever before.
Except. Except that, while some excellent SparcMacs will be released in MacWorld January 2008, this will not be enough. So, even as we speak, Jobs is preparing his speech for WWDC 2008. And it's a major one. He'll be announcing a complete transition from SPARC, to 6502 based CPUs.
Now, I know what you're thinking. 6502s are 8 bit right? And they're capped at 2MHz? Well, there's the 65816, the engine behind the Apple II GS which should tell you differently. But there's more. Since the Apple II GS was discontinued, a band of engineers has, in total secret, working with the same guys who ported Mac OS X to Intel, come up with a 64 bit version of the 6502, that runs at 8GHz, and is capable of 8 giga-MIP performance. Per core. And we're not talking about a single core design either. Nor a dual core. Nor a four core. This baby, the 65864256, has two hundred and fifty six cores. Yet it barely sucks a microwatt at peak usage.
The first 65864256 based laptops will come out at MacWorld 2009.
To be followed by a startling announcement at WWDC 2009.