First and final paragraphs of a Walt Mossberg review follow below. I had better results upgrading an approx. 2-year-old Dell laptop from Windows 7 to Windows 8 Pro, but I also generally agree that most people will probably benefit from either buying a new PC or sticking with Windows 7, on older PCs. My nit of the week: I purchased Windows 8 Pro on DVD from Amazon, for $39.99 after rebate, to upgrade the ~2-year-old Dell, and then used the same DVD to upgrade an older (~4-year-old) Dell laptop. The second upgrade went smoothly, and the older laptop runs much more smoothly, but I can't find a way to take advantage of the $39.99 upgrade offer that will expire at the end of this month, for the older laptop (i.e., to purchase a discounted license key for a laptop already running Windows 8 Pro); when I run the download app Microsoft provides for the upgrade, it does an obviously useless compatibility check and ... informs me that the upgrade option is "not available in my country." I can instead pay ~$70 for a new key with no discount, but since that'd be ~23% of the purchase price of a new low-end Windows 8 laptop, I'll pass...
"If you’re thinking of upgrading your PC to the new Windows 8, be prepared for hassles and disappointment, especially if the computer is more than a year or two old—even if it technically meets the basic requirements to run the new version.Upgrading to Windows 8 - Not for Old-at-Heart PCs - Walt Mossberg - Personal Technology - AllThingsD
"The industry really wants you to get Windows 8 via an all-new PC, and most people who adopt it will go that route. But, if you don’t, or can’t, and have even a three-year-old PC, you may want to just stick with the Windows you’ve got."