Dopey but charming, this romantic comedyabout a San Francisco wedding planner (Jennifer Lopez) experiencing love at first sight vis-a-vis a pediatrician (Matthew McConaughey) who turns out to be the expectant groom in one of her assignmentsdraws much of its allure from the two leads. Most of the remainder comes from a clear desire to emulate and approximate various second-tier studio musicals and comedies that one might associate with the early 50s. This never rises above such treacle but happily lives up to it every chance it gets. With Bridgette Wilson-Sampras, Justin Chambers, Judy Greer, and Kathy Najimy; written by Pamela Falk and Michael Ellis and directed by Adam Shankman. 100 min. (JR)