The Siri vs. Cortana commercial from Windows shows a conversation between the two rival personal assistants. Although Siri used to be the most impressive personal assistant out there, she's presented as a bit of an airhead in this ad. It begins with Siri looking at her own reflection in the mirror and singing "I Feel Pretty" to herself.
Cortana comes alone with a smoother sounding voice and promises to aid Siri with booking her manicure and pedicure. The ad humorously points out that the reason why Cortana's voice is so crystal clear is because she has two speakers—Siri only has one and she's sitting on hers. Fortunately these two only have their voices to go at each other with, otherwise the ongoing Microsoft and Apple rivalry between the two phones could get a little scrappy.