Our little girl is growing up. “Mine,” the first single from Taylor Swift’s forthcoming album, “Speak Now,” leaked out today, leading her  label, Big Machine, to rush release the tune to radio today, a few weeks ahead of schedule.

The uptempo track is vintage Swift about romantic love, not too explicit—the most he does is put his arm around her, but there are lines that the 16-year-old Swift couldn’t have written that the now 20-year-old Swift can easily tackle including “there’s a drawer of my things at your place,” which would indicate that  she’s actually, gulp, spending the night with her beau.

On a more quotidian note, she sings, “We’ve got bills to pay,” which would indicate someone in their early 20s, out on their own for the first time.

The tune, which Swift wrote by herself instead of with a co-writer as she has previously, also takes a different perspective than her earlier songs in that she is in a romantic relationship looking back to the beginning of their time together.

Melodically, it’s stripped down enough for country, although pop will have no problem playing it either. There are also catchy, layered vocals at the end that sweeten the song’s appeal. Swift’s label, Big Machine, in an effort to make  country radio, which broke Swift, still feel like she belongs to them, serviced the song simultaneously to iTunes and to country radio, but not to other formats.

In addition to the gargantuan pressure Swift—or any artist—would feel to follow up such a huge album as “Fearless,” Swift has a double monkey on her back: she has to transition to an adult artist. It’s not quite the hurdle that a Disney artist like Miley Cyrus has to overcome, but Swift has written songs that reflect her peer group: teen girls—such as the girl in “Fifteen” who regrets losing her virginity or the non-cheerleader who yearns for the popular boy in “You Belong With Me.”

The challenge before her is to show growth and maturity as she moves into her 20s, while not ignoring or alienating the younger set. It’s not an issue her peers, such as Lady Antebellum’s Hilary Scott or Kellie Pickler face since they are a few years old, but, more importantly, have always approached romantic relationships in song as adults as opposed to someone in the first blushes of puppy love. If “Mine” is an indication, Swift looks to have crossed that bridge successfully.

Listen to "Mine" below. It's not the clearest version Swift sounds higher than normal, which we believe is due to the poor quality of the copy. We'll switch it to a clearer version when we can. What do you think of "Mine."