Last March, in his second-to-last Apple keynote address, Steve Jobs uttered the phrase "post-PC world." Many snickered. But now, after the release Wednesday of iOS 5 — Apple's new operating system for the iPhone, iPad, and iPod Touch — the post-PC world might really be here. That's because this new software allows us to update, sync, and back up our mobile devices without ever plugging them into a computer. Does iOS 5 really signal the dawn of a new era in computing, or is this just another upgrade?

It's revolutionary... but imperfect: This latest update alters almost every aspect of Apple's mobile operating system, says Dan Moren at Macworld. "With iOS 5, it's possible, for the first time, to use your iPhone, iPod Touch, or iPad as your one and only device" — there's no need for a personal computer as an anchor. Things that would have formerly required users to hook up to a PC — like, say, making a photo album or a playlist — can now be done directly on your iPhone or iPad. But it's not "all sunshine and daisies." The buggy new software is actually "the least polished major iOS update in quite some time." 
"iOS 5 Review: Ambitious update rings in the changes"

This will change our lives: "iOS 5 is the update that changes iOS' fundamental DNA," says John Brownlee at Cult of Mac. Jobs was right about the "post-PC era." iOS 5 puts all your data in the iCloud and, with iTunes Match, you can access your entire music library from the cloud at any time — no need to pull out your connector cable. Everything syncs wirelessly. This is the future that Jobs envisioned, in which we aren't tethered to bulky computers. And that's not all. Apple has "added major new features to almost every core iOS app: Mail, Safari, Camera, Calendar, and more." 
"iOS 5: The software Steve Jobs always thought you deserved [Review]"

C'mon. It's not such a huge change: There's plenty to like about the new operating system, says Jason Parker at CNET. It integrates Twitter more seamlessly and adds basic editing tools to the camera. But even the ability to wirelessly activate and upgrade your phone without hooking it up to your computer is not "particularly novel." Android, Windows Phone 7, and BlackBerry OS 5 already have such capabilities. "iOS 5 seems more about fixing a lot of niggling annoyances than offering a completely new phone."
"Apple iOS 5 review: Modest, but definitely worthwhile"