It's late, the weather's nice (for the moment), and we've got big news so we're just gonna lay it on you: Mariah Carey has snatched the No. 1 song of the summer spot from the Black Eyed Peas, whose "Boom Boom Pow" is officially overplayed out - and faces an enemy from within: "I Gotta Feeling", by the Black Eyed Peas. Elsewhere, Cobra Starship and the Gossip burst the bounds of their respective genres to offer straight-up summer hotness, and Sean Kingston has us so ready to dance in front of the AC in our unmentionables.

Whether or not it's about Eminem, as some maintain (and the lyrics don't say Marshall Mathers to us - more like Stan), Mariah Carey's "Obsessed" contains one of the all-time great put-downs: "You're a mom-and-pop, I'm a corporation." (And you know Wal-Mart haters are turned on.) If nothing else, Mariah's an institution: Second only to the Beatles in No. 1 singles, she's the closest thing this summer has to a dominant (pun intended) diva - Keri Hilson's gonna touch her? Fergie? And, like the best summer tracks, this song's a shape-shifter: it's a slow jam, but with Gucci Mane on the remix; it's sexy, but a dis track; it's dark, but you'll sing along. Spin us right round, Mariah, and feel free to do so all summer.

1. Mariah Carey, "Obsessed"
Congratulations to Mariah on the Power Rankings' first-ever No. 1 debut. On a side note, another notch in Mariah's impressive SOTS CV are her gritty choices in remix partners: following in the footsteps of O.D.B. and Jadakiss come Gucci Mane and the official "Obsessed" remix.