This is such a great thread! My 2.5 yo DD currently has a thing for Daisy. I think it has a lot to do with her favorite show, Mickey Mouse Clubhouse.
She had a duck fetish in general when she was around 1 yo, so naturally she was crazy about Donald last year. She has since switched over her obsession to Daisy. When we were at WDW in September, she was able to walk with Daisy to her place under the Sorcerer's Hat. Talk about the thrill of her vacation! When we were there a couple of weeks ago, I bought her a small Daisy plushie toy at the beginning of the trip and it was her constant companion. I did notice that Daisy is one of the characters who is on the train at the park opening show at MK now (not sure if she has always been part of the show, but we did notice her a couple of weeks ago).