My baby girl is growing up

Miah told me yesterday that she doesn't like dresses anymore. She said they're itchy and not comfortable and she'd rather wear pants and jeans. She said that mostly grown-ups only wear dresses for really special occasions like once a year, and that most of the girls at her school don't wear dresses.
Miah has always been a very girlie girl. For the past 6 years she has LOVED dresses and skirts. I figured she would grow out of it someday, but now that the "someday" is here, I feel sad.
In December at her 6th Birthday party she had on this adorable dress with tights, and after her first friend showed up wearing jeans, Miah disappeared into her room and came out wearing jeans. I was shocked, but then realized what had just happened.
Miah and I have this special thing we do often, it's called cuddle time, but we talk, she begs me to do this with her. We cuddle together and then I say a series of "What do you like better" and I give her two things to choose from, she loves it, and she often responds, "both of them". Like do you like cereal or toast? do you like movies or books? do you like painting or soccer? etc.............
So yesterday when I said do you like skirts or dresses, I was expecting her to say "both of them" and she said, "neither, I like pants and jeans". So we talked about it for awhile, and she was so mature about the whole thing, I can't believe some of the amazing conversations I have with a six year old.