Miley Cyrus Dances, Grinds with Women at Britney Spears Concert >>Hollywood

Britney Spears made her Las Vegas debut last night at Planet Hollywood, and she had a very famous fan sitting front now:

Miley Cyrus!

The 21-year old was totally into a Britney track at one point, mouthing the lyrics and dancing along to the beat.

Later in the evening, she was then joined by a couple female dancers for Miley's second girl-on-girl experience of the week, following her much-publicized French kiss with model Cara Delevingne.

Watch Cyrus shake what her mama gave her while Spears struts down the stage now:

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  Miley Cyrus Dances to Britney Spears
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  Miley Cyrus Grinds with Women

As for how Britney herself did? Check out these videos from the concert:

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  Britney Spears - Do Something (Piece of Me Opening Night)
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  Britney Spears - Till the World Ends (Piece of Me Opening Night)