AC/DC's "Back in Black" album has reached another milestone: the shipment of more than 20 million units in the U.S.

The 1980 set is one of only a handful to have earned two Diamond certifications--representing 10 million albums shipped--from the Recording Industry Association of America.

With their schedule opened up by Lollapalooza's cancellation, The Flaming Lips [ tickets ] have moved up the recording sessions for their next album.

According to the band's official website, recent sessions so far have netted two new tracks, tentatively titled "Mr. Ambulance Driver" and "Space Bible," as well as a song for the "SpongeBob SquarePants" movie soundtrack.

No release date has been announced for the upcoming album, which will be the follow-up to 2002's critically acclaimed "Yoshimi Battles the Pink Robots."

Fatboy Slim [ tickets ] drops his fourth album, "Palookaville," on Oct. 5. It will be the producer/DJ's first studio set since 2000's "Halfway Between the Gutter and the Stars."

System of a Down has wrapped up pre-production work for their next album, and plan to record the set later this summer.

"There is a wide array of influences in our new songs," guitarist Daron Malakian said in a statement. "The influences range from Kraftwerk to Dark Throne to The Zombies to The Beach Boys, but it all fits together, it works."