It's about time! Mariah Carey and Nick Cannon finally had a big wedding celebration. The party was at Def Jam chairman L.A. Reid's house in the Hamptons, which was decorated with flowers and candles, a spy tells Page Six. Guests included Gwyneth Paltrow, Mary J. Blige, Kelly Ripa, Samuel L. Jackson, and Star Jones. And even the uninvited neighbors got the newlyweds a present -- a visit from the po-po! The shindig was apparently so loud that the cops were called to quiet it down.