Ready to partake in another installment of the UK's top talent show, Katy Perry and Cheryl Cole were both spotted arriving at "X-Factor" studios in London on Sunday (October 17). While Cheryl dressed casually ahead of her judge duties, Katy turned up a bit more glammed up as she happened to be the night's special guest performer. Once the gig got underway, Miss Perry took the stage in a sexy Lycra ensemble while treating the audience to her new single "Fireworks". Coming just ahead of her rumored wedding date of October 23, Katy also made sure to voice her hopes to be considered for a full-t...