Google has announced an ambulance support for video and voice chat in Google Talk on the Android platform. According to the company, the first device on which this functionality will appear will be the Nexus S.
The second nexus will receive this functionality along with the software update number 2.3.4 , already in the coming weeks. And later, and all other devices, on the 2.3+ platform (nothing is said about 2.2 and below). As stated, video chats will work both in Wi-Fi networks and in 3G and 4G networks.