BRITNEY SPEARS SLIPS INTO NUDE BODY SUIT AFTER OVER A DECADE.

Remember this nude body suit for her "toxic" video over a decade ago?

She slipped into something similar, for her Las Vegas opening show last night and she pulled it off real good.
According to TMZ;

Britney Spears blew everyone away during her Vegas debut last night ... everyone, but Katy Perry.

Katy was front and center for the "Piece of Me" show -- rubbing elbows with Miley Cyrus and Adam Lambert -- and while Miley danced her ass off, Katy couldn't seem less interested.

True enough ... Britney's no John Mayer, but come on Katy -- she's a much better dancer than him.

As they say ... you can please some of the people all of the time ...