Taylor Swift -- My Chest Is a Wonderland (Take That, John Mayer)

Even Taylor Swift's haters can't hate hate hate what she just unveiled at the Victoria's Secret Fashion Show ... serious cleavage!

For once, there was nothing prudish about the 24-year-old's outfit on stage in London. Instead, she opted for some sexy lingerie, and a Wonderbra-like lift, during her performance at the show.

A Vicky's Secret rep tells us the nightie/bustier thingy clinging to Swift was custom built for her bod.

So, welcome to Whapperville, Taylor -- and check out all the V.S. Angels who shared the stage with her.