Justin Timberlake may decide to reconsider his reported decision to switch careers from singing to acting after he reads the reviews for Bad Teacher , in which he stars with Cameron Diaz and Jason Segal. Actually Timberlake himself is getting OK notices -- critics particularly like a scene in which he sings an awful song off key -- but critics use the adjective in the title with abandon. Several compare it with another movie with that adjective in the title -- Bad Santa . Roger Ebert in the Chicago Sun-Times says that the new movie "suffers by the comparison. Its bad person [the Cameron Diaz character] is neither bad enough or likable enough." Ann Hornaday in the Washington Post observes that "it takes good filmmakers to make bad people if not sympathetic then at least interesting. Bad Teacher isn't good that way. It's blandly, boringly bad." The real problem, Claudia Puig suggests in USA Today is that "no one bothered to create anything beyond a vague outline of a superficial character." The fault, most critics agree, does not lie with the actors. Praising Timberlake's execution of one scene, Steven Rea remarks in the Philadelphia Inquirer, "Here, too, however, the writing isn't up to the performance." The movie runs only 92 minutes, something that critics can at least be thankful for. But Lou Lumenick in the New York Post wonders whether "the relatively brief running time suggest[s] the studio got cold feet in the cutting room." Of all the major critics, Manohla Dargis of The New York Times , ordinarily one of the toughest of the lot, stands alone in praising the film, which she describes as "the kind of broad comedy that threatens to get ugly and more or less succeeds on that threat." She concludes "With Bridesmaids still doing gangbusters at the box office, Hollywood apparently thinks it's time for the ladies to get their hands and other parts dirty. Well, if that's what it takes to get women out of the house, off the pedestal and into the same serious comedy club where the boys frolic and play, I say let her rip."