In a brilliant cost saving measure, the NYPD is borrowing metal detectors from New York City schools to set up in Times Square on New Year's. The Times reports that 240 metal detectors (about twice as many as last year) will be set up at various Times Square side streets to screen the tourists, teenagers, bridge 'n' tunnelers and drunks fool enough to do New Year's in Times Square. However, having metal detectors in Times Square around the clock would be problematic, with the Conde Nasties' stiletto heels and Black Israelites' swords just at the top of the list of "Things that are/contain metal in Times Square."
Other security measures being taken for New Year's in Times Square: Manholes welded; mailboxes, garbage cans, and vending machines removed; snipers on rooftops; hundreds of police officers on duty, many in plainclothes (Mayor Bloomberg said, "You're going to see a lot of cops there. There'll be a lot more cops that you don't see."). The Department of Homeland Security granted New York's request for extra air support, as if it was going to say no.
According to the Times Square BID, revelers start entering Times Square at 5PM, and 750,000 are expected. Find out more about what happens in Times Square on New Year's Eve here, like how "Pom-poms, Balloons, Hats, Glasses, Flags and Confetti Bags" are distributed at 8PM.