Katy Perry's "Firework" Performance for Ellen

Making her promotional rounds, Katy Perry recently paid a visit to the "Ellen DeGeneres Show" to talk about her new perfume, among other topics.

During the gig, Katy confessed her admiration for Gwen Stefani for being "effortlessly cool" while also performing a version of her hit song "Firework" to the audiences delight.

Aside from Miss Stefani, Katy interview with Maxim magazine in which she gave props to Lady Gaga and Ke$ha - though she said she's gotten past her Justin Bieber crush.

"I love what Gaga is doing, and I love what Ke$ha is doing," Perry dished. "I've known Ke$ha forever. She's actually in the 'I Kissed a Girl' video."

As for Bieber, the 26-year-old told, "I've said Justin Bieber [was my celebrity crush] quite a few times, but I think I'm over it now. I think it's probably safe to say I married my celebrity crush. Don't barf on this magazine."