Google started rolling out Android 2.2 Froyo OTA update for Nexus One users couple of days ago. If you haven’t got OTA update notification, you can download Android 2.2 Froyo on Nexus One and can install it manually. To download and update Android 2.2 Froyo for Nexus One (Manual Update), follow the steps:

1. Download Android 2.2 Froyo ROM (Google) (Filename: signed-passion-FRF50-from-ERE27.1e519a24.zip File Size: 44 MB)
2. Copy the zip file to microSD card of your Nexus One. (To make this easier, you could rename the file to something like Froyo.zip or Update.zip.)
3. Turn your Nexus One off, then hold down the trackball and press the power button.
4. When device boots, you will see a white screen with 3 Android logos on skateboards. Select “Bootloader”.
5. Then select “Recovery” in next screen, your phone will reboot. At this point you will see Android logo with exclamation sign in a triangle.
6. Then press the power button and volume up buttons at the same time.
7. Choose “Apply sdcard:<filename>.zip”. Here “<filename>” is the name of the file that you put onto your SD card in step 2.

That’s all what you need to do, now your Froyo update for Nexus One do the inevitable. Once it done, enjoy the new features that come with Android 2.2 Froyo.