The decision, which comes at a time of growing concern over cyber-security, applies only to the military's non-classified network.

But it could mean big changes for large portions of the armed forces, including the Marines, which had selectively banned social media on work computers.

The Department of Defense also had bans in place since 2007 on accessing certain bandwidth-gobbling Web sites like YouTube on its network.

"The purpose of the policy is to recognize that we need to take advantage of these Internet-based capabilities. These Web 2.0 tools need to be part of what we use," David Wennergren, a deputy assistant secretary of defense, told Reuters.

More: http://www.reuters.com/article/idUSTRE61Q07G20100227

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