Thanks to Mark Robinson for the tip: Microsoft has finally posted its Windows 2000 Readiness Analyzer, which will examine your current system and report potentially incompatible hardware and software. This software is also available during the Windows 2000 Setup process, but this quick download will allow you to determine compatibility before Windows 2000 arrives, giving you time to reconfigure your system if necessary or save a couple of hundred bucks if you decide not to upgrade.
Though the Readiness Analyzer is fairly thorough, it's worth noting that the results it gives aren't 100% accurate: Some hardware and software that it determines to be incompatible will, in fact, work fine with Windows 2000. And it's also possible that the tool will look over hardware and software that isn't compatible and give it a passing grade. But this program is an excellent first step to any Windows 2000 upgrade. If you're unsure whether Windows 2000 is going to work on your setup, it's also advisable to perform a dual-boot installation of Windows 2000 the first time you install just in case something goes wrong. That way you won't lose your old system.
The Windows 2000 Readiness Analyzer, a 2.6 MB download, is now available on the Microsoft Web site