Official ICS has been released for nearly a month officially to Nexus S, however I still haven’t receive any OTA notification, most likely it rolling out in United state first. Since I owned a T-mobile version Nexus S, i got a chance to install the official update from Google. It is easy  to upgrade from Gingerbread to ICS officially. Let’s follow and upgrade to ICS 4 now! Hurray..

How To Install Official Android 4.0 Ice Cream Sandwich On Samsung Nexus S?

1. Firstly, download the OTA ICS 4.0.3 package from Google Website. [Download available – 128MB]

2. Rename it to update.zip.

3. Copy it to internal storage on Nexus S.

4. Shutoff Nexus S, press and hold volume up and the power button to reboot to bootloader.

5. Select recovery by navigating volume up and down button, and press power button to select.

6. Press the power and volume up button again.

7. You should see the menu, select “apply update from /sdcard and choose update.zip.

8. Install it and reboot once done.

9. Done installation and enjoy your ICS on your Nexus S.

[Via xda] Thanks!!