Mr. Skin just received a screener of Powder Blue. The bad news is that the topless scene sounds kinda brief, but the great news is Jessica Biel does show her butt.

The full review can be found here, but here are the parts that mention nudity.

(1:08) Jessica Biel walks out on stage in a hooded jacket with a cigarette in her mouth for another routine. A guy lights the cigarette for her and we see her black panties as she swings around the pole. The hood comes off and the jacket is open enough to see the bra she's wearing as she smokes during the dance. Now Eddie Redmayne walks in and the dance is intercut with him watching her. The jacket finally comes off and she crawls across the stage. The bra she's wearing covers the top half of her breasts. More pole swinging including attaching herself to it upside down and sliding down it. Now, the bra finally comes off from behind. We see her left breast from the side. All this with her back turned to us. She's on her knees and begins to pour hot candle wax down her back. And then...the moment. She goes down to her side and turns towards the camera, first revealing her right breast and then both as she arches her back and stares directly at the camera as she notices Eddie Redmayne staring at her. She moves back up, her back now covered in wax and we get a nice shot of her left breast as she bends down to get another candle. She splashes some more wax on her front where we don't see anything and she ends her routine sitting there on stage in her panties and covering up her breasts with her arms.

(1:24) Eddie Redmayne and Jessica Biel approach each other. He takes off his shirt, then he helps her off with hers. She's wearing nothing underneath and we get a great look (albeit a little dark and just off to the side) of Biel's breasts before they begin kissing.

(1:27) Jessica Biel is standing at the window of the bedroom at night. We see her from behind and get a nice look at her bare buns before Eddie Redmayne gets in the way and covers her up with a blanket.