We've kind of lost count on the number of Froyo updates that have hit the Nexus One since it was introduced just slightly less than a month ago. You might have just gotten the recent Android 2.2. build FRF85, but Google is one step ahead and introduces build FRF91.
Engadget - Another day, another Froyo build. Now that Android 2.2 build FRF85 -- i.e. the big one that got pushed over-the-air to every Nexus One this week -- is out on the prowl, Google's taken it upon itself to release yet another update, FRF91.
Most Nexus One device should be getting this update over-the-air very soon. But if you're eager to try out this new update, we'll direct you to where you can get it (legit source, of course) over here.