The word on the wire is that Android version 2.2.1 is available for the Nexus One. I’ll state it now to avoid disappointment in a few sentences; It is not a major update. At a measly 3.9MB we suspect that this is a simple maintenance release, but as shown in the picture from Android Central, it will make your Nexus One say “FRG83”. Sweet.
Although Google have not released an official note regarding the update, nor is there an official ‘changelog’ to details what is new, really smart people at xda-developers are allegedly stating that this update ‘patches the vulnerability that allows Universal Androot to work’.