The purported Britney Spears demo of "Telephone"—originally written for Spears by Lady Gaga before Gaga hit it big—has leaked. That sound you just heard was "BritBrit" overtaking "Bieber" on Twitter. We have the track, and some theories.

Ah, the sound of what could have been. In a nutshell: Lady Gaga originally wrote "Telephone" for Britney Spears, who passed after making a demo. This weekend, claimed to have a copy of the previously-unheard recording and released a tagged snippet, saying they'd leak the whole thing for $750. Some poor soul ponied up the dough, and this is what we got:

Britney fansite World of Britney is denying that it's Spears. Perez Hilton says it is. We're running down the arguments:

Case For: Such a demo has been confirmed to exist.
Case Against: No word on how iLeaks got their hands on it. World of Britney, which claims to have heard the "real" demo, says there's no Autotune on the genuine article.

Case For: Britney-like inflection and vocal tics.
Case Against: Britney's voice is easy to mimic, and Autotune can mask mistakes.

Case For: It sucks, like everything else Britney's done since "Toxic."
Case Against: It sucks, just like it would if it were someone with too much time on their hands making a fake Britney Spears "Telephone" demo.

So what's the call? Well, first of all, "Telephone" is Lady Gaga's dumbest and worst song, so who cares. But really, we're agnostic on the question—the vocals are mostly so Autotuned that it's entered the weird negative zone where it doesn't matter who actually sings it since it just sounds like a computer.

Interestingly, rumors have held that a lot of Britney's vocals on her last second-to-last album, Blackout, weren't actually Spears—so this could be the "official" Britney Spears demo without actually having any Britney Spears vocals. Either way, someone paid $750 for this, which is just, you know, sigh.

Final Verdict: It's almost definitely Justin Bieber.

[Video via Teen Today; pics via Getty]