It's the same story as it was 23 years ago. In 1985, Texas Instruments (the ones that make great calculators) created a marketing campaign called "Dare To Compare". It pitted their PC against the IBM AT. The TI PC had a better monitor, better keyboard, and faster processor for the same price as the IBM AT. Guess what: nobody bought them. Why? Because everyone was already using IBM PCs.
Buy computer stuff based on how many other people are buying it. WordPerfect is better than Microsoft Word. On the other hand, I think it's stupid to use WordPerfect because when you try to exchange documents with the rest of the world (that uses Word), it's a problem. When you need to hire someone the odds are that they will know Word and not WordPerfect.
If Dell has a problem, 100, 000 people will scream and they will get it fixed. But if you buy a "better" PC from the shop down the street, you may be the only one screaming when you have a problem.
More tools are written for the most popular products. Need an Add-in for Excel? No problem? Need an Add-in for Quattro Pro? Good luck.
Is Leopard more stable and just plain cooler? Yes. Is Linux free and superior in so many ways? Yes. Which is the better operating system? Vista or Leopard, Linux? Vista is the best because more people use it.