"After months of speculation about his political future, Mayor Michael R. Bloomberg plans to announce on Thursday morning that he will seek a third term as mayor, according to three people who have been told of his plans. The extraordinary move promises to upend New York City’s political world. Right now, Mr. Bloomberg is barred by law from seeking re-election. But he will propose trying to revise the city’s 15-year-old term limits law, which would otherwise force him and dozens of other elected leaders out of office in 2009, the three people said. [...] If successful, Mr. Bloomberg would be only the fourth New York mayor in modern history to win a third term." [NYT]