Goal-line technology has been approved for use in the Club World Cup and, if deemed successful, the 2013 Confederations Cup and the 2014 World Cup, FIFA decided on Thursday. There were two different technologies that have been approved, and the CNN story about the announcement suggests both will be tried out.
Goalref uses a microchip that is actually placed inside the ball and uses magnetic waves to determine whether the ball has crossed the goal-line. Hawk-Eye, a technology already used in tennis, uses high-speed cameras and triangulation.
The pressure to approve goal-line technology has been building for several years after high-profile mistakes in the the World Cup and European Championships. The clincher may have come at the most recent European Championship when Ukraine was denied a goal against England. That prompted UEFA President Sepp Blatter to tweet out: "After last night’s match #GLT is no longer an alternative but a necessity."