From The Onion AV Club:

The NME reports that the Led Zeppelin reunion dates at London's 02 Arena it previously reported are, in fact, in bogus, according to Led Zeppelin's promoter. However, promoter Harvey Goldsmith did not specifically deny that a reunion of the band's three surviving members won't take place at some point. (A supposedly defunct band having a promoter is sort-of a big tip-off that's something's up.) Zep is also set to release its umpteenth greatest hits collection later this year, so a tour announcement might come around then.