A leading Beat poet, Gregory Corso, 70, died of prostate cancer on Wednesday. A member of the circle that included Allen Ginsberg (who was more political) and Jack Kerouac (who was more charismatic), Corso’s very hip canon included the 1958 “Bomb,” an ode to atomic weapons . . . South Florida hotel architect Morris Lapidus, 98, who designed the splendidly gaudy Fountainebleau and other flamboyant structures in the ’50s and ’60s (critics called his style “Bronx Renaissance”), died Thursday at his home in Miami Beach . . . ’40s MGM musical comedy star Virginia O’Brien, 81, whose nickname was “Miss Frozen Face” because of her absolutely deadpan delivery of her numbers, died at Southern California’s Motion Picture & Television Home on Thursday. Her movies included “Ziegfeld Follies” (in which she sang to Fred Astaire and Lucille Ball) and “The Harvey Girls” (in which she played a sister waitress to Judy Garland).