Should social networks release data?

The US government has subpoenaed the social networking site Twitter for personal details of people connected to Wikileaks, court documents show. Should social networks ever disclose such information to governments? and this leaves Wikileaks in a difficult position.

Twitter has been keen to stress that it complies with local laws, says Mr Cellan-Jones, but it has also been eager to promote Twitter's role as "a forum for free expression" in countries like Iran.

Our correspondent asks: "If confidential details of overseas Twitter users are disclosed to the US authorities, how keen will an international audience be to trust this or other American social networks in future?"

Should social networks give up data to help in legal proceedings? Or is it more important for personal details to remain confidential? Will this damage users' trust in social networks?