Britney Spears sings Telephone

After the success of Lady Gaga and a spoof version from Lady Gagita.... there was a Telephone version from Britney pala? Nice! Below is a leaked version and I effing love it!!!  And to think that it was just a Demo.
Apparently Lady Gaga wrote it for Britney but for some reason Brit Brit didn't used it because the last album was high on Womanizer. So Lady Gaga recorded it with Beyonce.