I heard about this from Billboard, who described it as:
A demo version of the purported first single off of Madonna’s next album has been leaked online. The retro-sounding “Gimme All Your Love” would be included on the singer’s 12th studio album, which will be released in spring 2012.
Retro-sounding? You mean like 1980s Madonna?
A description like that may tell you something about who actually leaked it. The best thing that could happen for Madonna in the age of Lana Del Rey is for people to notice a Madonna leak. She looked like an old cat on her last album cover.
…I liked Confessions on a Dance Floor.