The Nexus S may already be in line to get an Ice Cream Sandwich upgrade from Google itself, but why wait? An enterprising new member of the xda-developers forums, kwiboo, has pulled together a build of the recently open-sourced OS for both the Nexus S and Nexus S 4G. Note that this is the AOSP version, not the SDK port that was available last month. There are a couple of rough edges — such as USB mass storage compatibility and having to manually add your Wi-Fi network — but user feedback so far has been overwhelmingly positive and stability seems to be good enough to encourage even the casual upgrader to give it a try. If you think you're ready to make that leap to Android 4.0, hit the source below for the download link.