I'll switch to Apple because Apple has switched to Intel. As long as Apple stayed on the Motorola 68K, and later the PowerPC, there was no incentive to give up the rich technical ecology of the PC. The PC in the early years had its flaws, but ever since the PC platform incorporated PCI and AGP, and started to use USB and Firewire, the PC platform has been more than a match for anything Apple could provide in hardware. The only thing lacking was software, and I had no real love for OS 9 and earlier to make me tolerate Apple hardware.
But then Apple released OS X. OS X, as you all know by now, is essentially the Mach kernel with BSD wrapped around it. Beneath the very shiny (and very good) GUI beat the heart of a real Unix. Now I was faced with a tough choice: buy the OS I really wanted to run on an inferior hardware platform, or buy the hardware platform I wanted and run an inferior OS. I chose hardware every time because I could always hack the software sufficiently to give me 90% of what I wanted. But now that Apple has moved over, I should be able (in the near future) to have both the hardware and the OS I want.
There's one more thing that Apple brings to Intel besides its superior OS. It brings real innovation back into the PC market. My hardware platforms over the last five years have been hand built. I've either purchased locally or online (via Newegg) everything I've wanted to create my hardware platform, and then loaded the OS (Windows and Linux). I think the company most at risk in this game is Dell. I think they face pressure at the low end from Lenova (the folks who bought IBM's PC business) and Apple from the high end. And make no mistake. Apple selling quality Intel gear will eat into Dell's high-end sales. There's a lot of built-up animosity towards Dell, and Apple, if they're smart, will tap into this, especially in the corporate market. And don't kid yourself. When Apple finally delivers their Intel boxes in 2006, I'll be looking very hard to see if I can replace Dell in corporate accounts with Apple. I'll be looking real hard.