Google now begin rolling out "Android 2.2 (codenamed Froyo) to Nexus One users 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. In order to access the update, you'll 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 notification by the end of the week," noted Google.
More Info: Android 2.2 Platform Highlights