The New York Post's city editor, Dan Colarusso, surprised everyone by quitting his job last night—and we hear he didn't go quietly. "Devastated," is how one insider described Colarusso's staff. "No one's too happy, not a good day," we were told. Colarusso worked 12-hour days, six-days-a-week while steering the metro desk. Speculation is that he'd lost patience with the "ruthless" politics of Col Allan's shop. No official word of his departure has gone out, but the general consensus seems to be Colarusso won't have any trouble landing on his feet. When he was promoted to run the paper's metro desk, just last January, Allan praised the editor's "hard news sense and street smarts."