The General Services Administration has signed a contract to use mySQL. The GSA manages bunches of government services and databases, and is only one of the latest Federal agencies to dump proprietary databases for the Open Source database system. The Department of Defense, NASA, the Census Bureau, and Los Alamos National Labs are among current users.
Open Source software protects users to a greater degree from product obsolesence and constant "mandatory" upgrades that typically involve big fees. MySQL AB will provide GSA with service and support of the database system, but the code itself is freely available. Using Open Source is not free; you still have to update and maintain the system, like any commercial product, but code upgrades and security patches are free and allows a company or organization to spend IT dollars differently, and provides more flexibility in decisionmaking.