In this scenario, which is the publicly announced one, Apple's chip supplier change matters only to IBM, the dumped supplier, and to Intel, which has picked up a nice new OEM account. Software developers who work with Mac OS will need to make changes, but they survived the change from Mac OS 9 to OS X, so they're used to this sort of thing and, despite grumbling, will come out unscathed.
Running Windows on Apple hardware
But imagine being able to run Windows on Apple hardware!
Actually, you can do that now with Microsoft's own Virtual PC for Mac. So why would Microsoft worry about making sure Windows runs on Apple hardware? Wouldn't they just issue a new version of Virtual PC for the new Apple hardware architecture?
This product, which includes an OEM version of Windows, costs hardly more than Windows by itself. It's on the market now, and has been available for quite a while. But you don't hear dire warnings about what it means for Linux, do you?
There are several Linux distributions that run on current Apple hardware. Surely Microsoft has at least a few developers as smart as the average Linux kernel hacker or driver writer. So if Microsoft felt it was a market necessity to have Windows run directly on Apple hardware, wouldn't it already have an "Apple hardware" version of Windows available?
What if Apple sells Mac OS for non-Apple PCs?
Imagine being able to buy whatever PC hardware you wanted -- or at least select a box from one of a long list of "approved" vendors -- and install Mac OS X on it. Suddenly Mac would be a viable competitor for Microsoft.
And desktop Linux would get lost in the crossfire.
Like it or not, there are many more applications available for Windows than for Mac. This alone would keep the vast majority of computer users tied to Microsoft. Some would undoubtedly switch, and Mac OS would become more popular than it is now, but Microsoft wouldn't suddenly go bankrupt and be forced to auction off its Redmond real estate.
What would happen, though, is the idea of operating system choice would start to spread. Right now -- again, a "like it or not" situation -- for an awful lot of people Windows is "the" operating system.
Probably half of all desktop Linux advocacy right now is devoted to saying, "Yes, there is an operating system other than Windows that runs on most of the same systems that run Windows."
If Apple wants to take on this burden, it's fine with me. I'll cheer Apple, loudly, if and when I start seeing ads telling the desktop-using public they now have a choice in PC operating systems for common, low-cost x86 hardware.
Once the idea of operating system choice goes mainstream, Linux will no longer be something for oddballs -- at least on the desktop -- but just another choice. This will make it more accepted, and may even convince more commercial software developers to deliver Linux ports at the same time they work on Mac ports of their products.
I have never been convinced that Linux needs to have a majority of the desktop computing market to be considered "successful." As long as it's popular enough -- and has enough and smooth enough applications -- to be a rational mainstream computing choice, and instead of a computer monoculture we have open standards that work across multiple platforms, Linux will do all I need it to do, at a cost (free) that neither Windows nor Mac OS is likely to beat.
And if this happens, I hope we all remember to send Steve Jobs flowers -- or at least a nice little "thank you" note.