Apple just announced the switch to Intel processors.
What it means:
You’ll want to buy a new Mac. Well, of course — but you always want to buy a new Mac.
Update: But you won’t want to wait to buy a new Mac. If you need it, buy it; if you don’t need it, wait.
You’ll have to buy all new versions of your software. Yep. Two years from now when the Intel Macs come out, if you want new versions of Office and Photoshop and whatever else you own, you’ll probably have to shell out upgrade fees. All the more reason to move to open source software.
What it doesn’t mean:
Existing Macs will be obsolete. No more so than any computer becomes “obsolete” the moment you buy it. Developer software “fat binaries” will allow programs to run on both platforms. Sort of like Carbon and Cocoa now, but even more transparent.
Windows programs will work with OSX. This should be obvious, but to many people it isn’t. Most software is written for the OS, not the chipset. Getting Windows software to run on it will still require an emulator.
Update: There is some suggestion that Mac Intel hardware will be able to run Windows and OSX simultaneously. This sounds unlikely to me, though the underlying software abstraction layer might make it possible. The new machines should be able to dual-boot to Linux or OSX. Oh, or that other atrocity, Windows. By the way, by the time those machines are released — Longhorn still won’t be available.
You’ll be able to run MacOS on any Intel PC. Nope. There will be new Intel-based Macs made by Apple, and they may have unique hardware that OSX will refuse to run without. Of course this hardware key may be subject to workarounds, since Darwin runs fine on x86 hardware now, for free.
Standard PC hardware peripherals will work with OSX. Not necessarily. There will still need to be software drivers for every peripheral, just as there are now. Drivers should be standardized, especially in cases where the proprietary version does nothing above and beyond the standard.