It feels like the biggest patch release yet.
When I upgraded to iOS4, it felt like a new device. In fact, the strain it put on my old 3Gs required an eventual upgrade to iPhone 4. But iOS 5 is very different. It's quiet. The main theme I can ascribe to it is that it fixes so many of the deficiencies that the iPhone had. Note that: it fixes them. Not revolutionary; evolutionary.
Notifications that take up the whole screen? So last decade; gone. Can't use any tone for system events? Ok, now you can. Rich text email? Welcome to the 21st century. Lots of things like that. Just...fixes that should have been done all along.
Even the new features are understated. Take iMessage. Looks and feels like SMS; the magic happens behind the scenes and is largely invisible to the user. iCloud's big impact? Background synchronizing. Reminders? Geofencing is very cool and slightly creepy, but it works well, without fanfare. And future abilities to update iOS without using a computer is great, but not yet needed.
I am (uncharacteristically) not complaining: iOS5 is solid, snappy, and fixes a lot of the problems. Are there some annoyances still? You bet. How about the introduction of syncing to your computer over wi-fi (another one of those features that just should have been there since day 1), but only if you plug your iPhone into power? Is Apple so worried about the battery impact? And then there is the phantom accessing of the location services: with barely any apps running, the iPhone now shows it's communicating location to...something, but no idea what, and not always. And while I like the idea of Newsstand, I have a special folder that I throw most of the "helpful" apps Apple automatically includes, but Newsstand can't go in there. Why? Because it's actually a folder, despite not looking like all other folders.
Look, given more time, I am sure I will find more interesting wrinkles of the post iOS5 world, but today, the future arrived not with a bang, but a quiet, elegant massive patch that smooths out many of the deficiencies of the past. It doesn't set the bar, but it definitely quiets many of the complaints thrown at it before. The sad part is that a major Apple release's best praise has to be "it's solid." Not a bad thing (ask Mercedes if they mind hearing that), but not the game-changing we all have come to expect. Maybe that will come over time, which would be appropriate for a luxury brand.