Probably not the best time to launch a medical drama based around a plucky and opinionated nurse. After all, Showtime just last week launched Nurse Jackie , its own series about, you got it, a plucky and opinionated nurse in a comedy series that's intelligent, gripping, and utterly unforgettable. The same, sadly, can't be said for TNT's Hawthorne (I flat out refuse to capitalize the RN--for registered nurse, natch--in the series' title), which launches tonight on the cabler. Created by John Masius ( St. Elsewhere, Dead Like Me ), Hawthorne pales in comparison to the similarly-themed Nurse Jackie . It also tries to take a more serious tack with its handling of professional nurses than the Edie Falco-led Showtime series and yet feels all the more tired and staid as a result. Jada Pinkett Smith ( The Matrix ) stars here as Christina Hawthorne, the widowed Chief Nursing Officer at Richmond Trinity hospital who has to contend with a headstrong daughter (Hannah Hodson), a b