Katy Perry, Pitbull, Britney Spears Battle For Summer Jam Crown

Well, school's out and summer is officially here, which means it's time to handicap the race for Summer Jam 2011 — the annual sweepstakes of sweaty, sex-drenched (and, this year, sax-heavy) songs that turns our nation's finest beaches and waterfront drinking establishments into an all-out battle for summer-soundtrack superiority.

Last year, it was Katy Perry who emerged victorious, thanks to "California Gurls," her slinky ode to daisy dukes and melting popsicles, and she's back to defend her crown this summer with "Last Friday Night." But she'll face considerable competition from a host of big-name stars — Lady Gaga, Britney Spears, Nicki Minaj and Adele — each of whom are looking to take home the title. And even if she manages to outgun them, will Perry have enough left in the tank to takedown the suddenly sizzling Pitbull or the unstoppable LMFAO? We'll just have to wait and see.

And with the action just getting under way, here's our up-to-the minute standings in the Song of the Summer Sweepstakes. If there's a song we've missed, you can let us know about it via Twitter, using the hashtag #mtvsos, or in the comments below. So without further ado, let's slather on some sunscreen and get to the jams!

1. Katy Perry, "Last Friday Night (T.G.I.F.)" : She dominated the summer of 2010 with "California Gurls," and now Perry is out to make it two in a row with the ebullient "T.G.I.F.," the 183rd single from her Teenage Dream album. It currently sits at #4 on Billboard 's Hot 100, and it seems like it's only a matter of time before it makes the leap to #1. Call it manifest destiny.

2. Pitbull (featuring Ne-Yo, Afrojack and Nayer), "Give Me Everything" : Perhaps the only man standing between Perry and her second-straight Song of the Summer crown is the suddenly ubiquitous Pitbull, whose "Give Me Everything" just went to #1 on the Hot 100. It's from his well-received, club-approved Planet Pit album, and its success only validates the fact that the Miami rapper may finally be having his moment.

3. LMFAO (featuring Lauren Bennett and GoonRock), "Party Rock Anthem" : Aptly titled hit from America's leading purveyors of sublimely stoopid odes to inebriation, "Party Rock Anthem" is basically the spiritual sequel to all of LMFAO's earlier jams (like "I'm in Miami, Bitch" and "Get Crazy," the theme from MTV's "Jersey Shore") only, you know, times one thousand.