Starz is streaming the uncensored first episode of Spartacus: Vengeance free (for people in the US only) at http://www.starz.com/originals/spartacus/videos/#/episode-201/. Here is a review of the nudity in the episode from wda258 at Celebtop.

Tits and extremely, extremely brief full frontal from Viva Bianca. You get a fleeting glimpse of her bush as she spins around. Probably a merkin again.

Tits from extras in the colosseum crowd.

Full frontals from several extras in a lengthy brothel scene.

Tits and a near full frontal from Lucy Lawless. She's getting out of a bath and the camera cuts away right before she gets out completely.

Brief tits from Katrina Law.

There's also a flashback of the scene in season one where Spartacus screws Illythia.