It’s been a long time since we’ve seen Julia Roberts in an “awkward” role (think “Steel Magnolias”), and this one fits the bill. Formerly fat, consistently self-conscious Kiki (Roberts) will do anything to keep her personal assistant job with megastar Gwen (Catherine Zeta-Jones). But when legendary press agent Lee Phillips (Billy Crystal) enlists Kiki to help Gwen and her estranged husband, Eddie (John Cusack), put on a happy face for a press junket, her talents are taxed — especially when her friendship with Eddie takes an amorous turn. Written by Crystal and directed by Joe Roth, “America’s Sweethearts” has no shortage of star power. But it can claim no greater coup than casting America’s current sweetheart as its lead.