Well, there you have it.
Conventional wisdom is that had Microsoft just shipped.1 a year ago—or perhaps just held off on Windows 8 until 2013—that everything would have been fine: Users would have embraced the new system, PC sales never would have tanked to the extent they did over the past year, and Microsoft's position in this new mobile world of computing would have been less tenuous. That's not really true, of course, but I do think that Windows 8 would have benefitted from another year in the hopper. More to the point, Microsoft could have avoided some unnecessary hurt feelings with users if it had simply listened and then shipped instead of vice versa.
We can't reverse history, and the extent of the effects of Microsoft's mistakes with Windows 8 won't be truly known for years to come. But if you view Windows 8.1 as an apology, as I do, then let's at least give the company some credit. They did listen, if belatedly. And while the leadership teams at Microsoft still believe firmly that the future is mobile devices not computers and online services not local data, it is meeting the realities of today's customer base in the middle. So we get the Start button but not the Start menu. We get a better desktop with reduced Metro meddling but not the full split some wanted. We get a system that is still very much a compromise, though Microsoft will of course market it as the best of both worlds.
To the cynical, Windows 8.1 is a better version of something that is still less than ideal. And while I can be as cynical as anyone, I actually use this thing every single day, and do so largely on traditional (non-touch) portable and desktop computers. And you know what? Windows 8.1 is an improvement. It's better. Period, with no caveats. It's better than its predecessor, and that's true whether you've embraced the future or are stuck in the past.
If you use Windows 8—or Windows RT, of course—Windows 8.1 is a no-brainer, a free upgrade that will make the entire system better than before. So upgrading to Windows 8.1 isn't a question of why or how. It's just a question of when. And the answer is: As soon as you can.
If you are using an older version of Windows, it's fair to say that Windows 8.1 doesn't change the overall value proposition. This new OS is still a weird hybrid of mobile and traditional PC computing. But the lines are starting to blur, and certainly the cross-environment transitions are less jarring—and less frequently needed—than before.
Windows 8.1 is a much-appreciated improvement. Highly recommended.