BSPEARSPINK050708_01.jpgBritney Spears BSPEARSJACKET0507_008.jpg What, you thought the boost Britney Spears got from her expanded custody with Sean and Jayden was a one-day thing? Well, guess again!

Britney was all smiles and politeness yesterday afternoon at Bally, keeping a big, sincere grin on her face as she made her way in to work out.

After that, she stopped home around 9 pm and then left at 10:15 for the studio later that night! Then, Brit was downright serious, heading straight into the booth at Conway Studios in West Hollywood, and staying put for a few hours of hard work.

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