Unlike me, some sensible people tend to wait for a .1 (or "dot-one") release of any software before committing to it, the idea being that major bugs that invariably ship with the first .0 version are worked out in the update. Looking at Apple's release notes for the iPhone 2.1 software released last week, it appears the sensible people can finally move on up.

The update is available for all iPhone owners, including those still running iPhone 1.0 software, and addresses a number of high-profile bugs and annoyances. (Apple has even listed them online and in the release notes.)

Unlike the iPhone 2.0.1 and 2.0.2 releases that provided merely "bug fixes," iPhone 2.1 addresses annoyances I and others encounter on a day-to-day basis. For example, the SMS and Phone/Contacts applications no longer dawdle when locating contacts. The time to back up the iPhone during sync is "dramatically reduced;" although I found backing up to be sluggish at times, I know people who would wait up to two hours for the backup to finish. If you have many third party applications installed, Apple claims it has fixed bugs that caused hangs and crashes. Apple also claims a "decrease in call set-up failures and call drops," which I hope also translates into better 3G performance in general - initial reports indicate that this is the case. This release also adds the Genius feature found in iTunes 8 and the iPods announced this week (see "Apple Reveals New iPod nano and Update iPod touch and iTunes 8 Adds Genius; iTunes Store Adds HDTV and NBC, 2008-09-09).

And now, finally, when you install new applications, the iPhone retains the placement of your application icons instead of jumbling them up. I'm already more calm.

iPhone 2.1 rolls in a handful of security fixes as well, including a resolution for the workaround that bypassed the Passcode Lock feature. Other changes include a way to prevent TCP spoofing by randomizing TCP initial sequence numbers, better application sandbox behavior, fixes to CoreGraphics, a fix to prevent DNS cache poisoning, and better CSS handling in WebKit.

iPhone 2.1 is available via iTunes as a 231 MB download; after connecting your iPhone, click the Update button on the iPhone Summary screen.