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Reports show that Adele was seen at Abbey Road Studios earlier this month, where composer Thomas Newman spent time working on the score for Skyfall! Adele also previously hinted that she was involved in music for the film when the singer told British talk show host Jonathan Ross last fall that she was planning to record one song before the end of 2011 and that it would be “a theme.” She added, “Wow, that’s really giving something away.”
So it's not like we weren't 99.9% sure that Adele was doing the theme song for this movie, but it has finally been confirmed for real! Roger Friedman, over at Showbiz 411, confirms that Adele will be featured prominently on the "Skyfall" soundtrack. He also says he's heard the song, and that it's a show-stopper.
He also revealed that the theme is going to be called Let the Skyfall. The lyrics include this chorus: "Let the sky fall/Let it crumble/We will stand tall/And face it all/together.”
Source: The Wrap