Even though I saw "Moulin Rouge!" way before any pictures of Arena Tour 2007, I didn't notice the similarity in the swing scene! ^^ That'd be interesting to see Ayu sing "Diamonds Are a Girl's Best Friend." 
Raelian, after looking at your post, I never realised how much musical inspirations there were in her tours! The "Come What May" and "INSPIRE" outfit are certainly similar, as is the "Prima Donna" outfit/"HAPPY ENDING" outfit and the ballet after "Ill Muto"/"M."
Hmm... After seeing how similarities are found in "Moulin Rouge!" and "Phantom of the Opera," something tells me I'll expect a good answer from my submitted "I want to ask Ayu this!" question ("What musicals have you seen?"). That is, if it's even read.