Masters writes:
 
As any weather aficionado can avow, Earth’s most iconic weather record has long been the legendary all-time hottest temperature of 58°C (136.4°F) measured 90 years ago today at El Azizia, Libya on September 13, 1922. One hundred thirty six degrees! It’s difficult to comprehend that heat like that could exist on our planet. For 90 years, no place on Earth has come close to beating the unbelievable 136 degree reading from Al Azizia, and for good reason–the record is simply not believable. But Earth’s mightiest weather record has been officially cast down.
 
Today, the official arbiter of Earth’s weather records, the World Meteorological Organization (WMO), announced that the all-time heat record held for exactly 90 years by El Azizia in Libya “is invalid because of an error in recording the temperature.” The WMO committee found five major problems with the measurement.
 
Most seriously, the temperature was measured in a paved courtyard over a black, asphalt-like material by a new and inexperienced observer, not trained in the use of an unsuitable replacement instrument that could be easily misread.
 
The observer improperly recorded the observation, which was consequently in error by about 7°C (12.6°F.) The new official highest hottest place on the planet is now Death Valley, California. A remarkable high temperature of 56.7°C (134°F) was measured there on 10 July 1913, at Greenland Ranch.
http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2230

It's about time - ridiculous that it survived so long really. I also know there is considerable scepticism over the Death Valley reading in 1913, expressed by a  number of experts. One picture of the enclosure (if genuine) taken a dozen years later shows the enclosure being much too close to the ground.