Apple late last night released iPhone OS version 2.2 for all iPhone and iPod Touch models. It's available now by going into iTunes, connecting your device and selecting Check for Updates.
2.2 Adds the following features:
* Enhancements to Maps
o Google Street View*
o Public transit and walking directions
o Display address of dropped pins
o Share location via email
* Decrease in call setup failures and dropped calls
* Enhancements to Mail
o Resolved isolated issues with scheduled fetching of email
o Improved formatting of wide HTML email
* Podcasts are now available for download in iTunes application (over Wi-Fi and cellular network)
* Improved stability and performance of Safari
* Improved sound quality of Visual Voicemail messages
* Pressing Home button from any Home screen displays the first Home screen
* Preference to turn on/off auto-correction in Keyboard Settings
For details on the features, head on over to http://www.apple.com/iphone/softwareupdate/.
One note -- if you have a jailbroken phone, don't apply this update yet. Wait for those crazy kids to update QuickPwn/WinPwn or whatever you use to work with 2.2. If history holds it will only be a few hours.