The Nexus S was supposed to be the definition of Google's perfect phone circa late 2010, so we can't imagine that too many at the Googleplex are enthused with the potential impact of a new custom ROM from Baidu. China's search giant has replaced many of the stock Google apps in Android 4.0 with its own examples, ranging from media players through to navigation. Google will take some consolation from knowing that the firmware can't be pushed ou