This dress, which I read is custom, feels like she said, "I'm really into American Hustle right now but I need breast support," and this was the best anyone could do. It's VERY disco. Kind of like if Glinda the Good Witch teleported herself to the '70s and decided it was time for a mojo change. I like the idea, but don't love the panels of fabric that AREN'T sparkly -- they're getting in the way, for me -- and I also think the bodice might not be cut right for her. Which is interesting given that if it truly was custom, then the whole THING was supposed to be cut right for her. It's theoretically sexy but perhaps matronly in practice, which is bizarre.
I like the ring, but mostly this is to give you a close-up look at the material. I just want to take this fabric and re-conceive the entire thing.
Her hair is under the illusion that she's competing in Miss America fifty years ago. Whatever that is on top of her head looks PARTICULARLY synthetic in that lighting, which is also distracting.
Maybe the very teeny nature of her accessories -- pretty though these earrings are -- is what's contributing to the dress as a whole looking old on her. She didn't do ANYTHING to give it youth and spunk, and Katy Perry is someone who has a personality that doesn't need to be dimmed into something that would work best on a stage while a lacquered emcee asks what she wants for Christmas and she replies, "World peace."