Jenny McCarthy, the ubiquitous December Playboy covergirl who departs her post hosting MTV’s “Singled Out” in February, will front her own sketch comedy/variety series for MTV, which carries the tentative title “The Jenny McCarthy Show.”Produced by Joel Gallen’s Tenth Planet Prods., the show has been given a 22-episode order and heads into production in Los Angeles on Jan. 13 for debut on the Viacom-owned net as early as mid-February. The 24-year-old McCarthy heads the half-hour as hostess and comedienne, leading a five-member comedy ensemble through various sketches, film shorts and parodies (or “little Jenny movies” as Gallen describes them) and comedic vignettes. Each episode is also slated to feature a live musical performance from an up-and-coming band and a McCarthy monologue. “The Jenny McCarthy Show” is the first of McCarthy’s two-series deal signed with MTV last July. The second will be a network sitcom made through MTV Prods.