What critics are saying about Madonna's new music

Madonna surprised fans Saturday by digitally releasing six new songs.

The move came after demos surfaced online earlier in the week -- much to Madonna's own surprise. The 56-year-old pop star had planned to officially unveil her new music in 2015.

"I was hoping to release my new single 'Living For Love' on Valentine's Day with the rest of the album coming in the spring," she said in a statement. "I would prefer my fans to hear completed versions of some of the songs instead of the incomplete tracks that are circulating. Please consider these six songs as an early Christmas gift."

The set features the anti-drug track "Devil Pray," the dance song "Illuminati" and a duet with Nicki Minaj, "B---h I'm Madonna."

Madonna linked up with collaborators Diplo and Kanye West on the set, which is due out in March. The album was recorded in London, Los Angeles and New York. It's her first release since 2012's "MDNA."

The set hit the top of iTunes within hours, and some early critics have already weighed in on Madonna's latest:

Jim Farber of The New York Daily News wrote, "The best of the new songs present the 56-year-old Madonna in a way that's finely tailored to her essential style. They fit perfectly into her history of impeccably-produced pop."

"The Kanye-produced Illluminati (with Madonna reciting a list of all the ways most candidates are not really part of the classically defined Illuminati, though they may be part of the paranoids' new world order) is colder and harder sounding, in the way of West's own recent work," noted Bernard Zuel of the Sydney Morning Herald. "There's some edge to it but not much menace that would really thrust it into compelling."

So, will Madonna head out on tour to back her new music? She told Rolling Stone, "I'm thinking about it. Right now, the deadline of getting this music out for iTunes was a 50-yard dash."