Facebook talks up need for virtual reality, big tech bets

By Alexei Oreskovic SAN FRANCISCO (Reuters) - Virtual reality, artificial intelligence and drones will enable Facebook Inc to create a more lifelike and useful social network, the company said in its clearest explanation so far for technology projects that have puzzled some investors and analysts. Facebook executives made the case on Thursday, at its annual developer conference in San Francisco, that initiatives such as its $2 billion (1.3 billion pounds) purchase of virtual reality headset make