Round 6: Hardware compatibility
There's no question that hardware compatibility was initially a sore spot with Vista. This was particularly true for mobile users who had to suffer through a variety of functional and operational problems as they waited for updated device drivers. And some of us are still waiting: I, for one, have yet to find a feature-complete video driver for my Dell XPS M1710, and I consider myself to be a fairly resourceful fellow.

But beyond scarcity, there is the issue of revalidation. Most sane IT shops have implemented strict rules regarding what is and is not an accepted hardware configuration. Departments with names like "PC Engineering" spend copious time testing and certifying specific component combinations, isolating problem configurations, and feeding the necessary troubleshooting guidelines to their help desks. A migration to Vista means repeating these steps, and then some, while the immaturity of the Vista driver base will have IT racing against a moving target.

Windows XP, by contrast, has a mature and well-vetted compatibility base, with broad support from virtually every manufacturer. And while Vista will almost certainly catch up in time, as things stand right now, every new device insertion is a bit of a crapshoot. Just the other day I was puzzled when my Vista-equipped notebook wouldn't recognize a generic HP LaserJet 1200 printer.

Decision: When's the last time you worried about driver support under Windows XP? With an installed base into the hundreds of millions, chances are you'll still be finding XP drivers long after Vista's grandchildren are being put out to pasture.

Round 1: Security
Round 2: Manageability
Round 3: Reliability
Round 4: Usability
Round 5: Performance
Round 6: Hardware compatibility
Round 7: Microsoft software compatibility
Round 8: Third-party software compatibility
Round 9: Developer tools support
Round 10: Future-proofing