It is now officially confirmed that final Android 2.2 Froyo build is out and this time it is FRF85B.
Previously we saw beta builds like FRF72 and FRF83 rolling out but this time Google also tagged this build as the “final” one.
According to Google: 
Starting today, Nexus One users will begin to receive the Android 2.2 (codenamed Froyo) over-the-air software update on their phones. This update provides some great new features including support for making your handset a portable hotspot and support for Adobe Flash within the browser. For a complete list of everything we’ve included in Android 2.2, please see the Android 2.2 Platform Highlights.
In order to access the update, you will receive a message on your phone’s notification bar. Just download the update, wait for it to install, and you should be all set. This update will be rolled out gradually to phones – and most users will receive the notification by the end of the week . We hope you enjoy these new features.
We are not sure if you are going to get this OTA update on your rooted Nexus One. But you can always look for a custom Android 2.2 Froyo ROM that has FRF85B bundled with it.
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