OK, you know Kidz Bop is getting surreal when the "By Kids, For Kids" outfit starts covering, well, kids. How old is Miley Cyrus anyway? The Jonas Brothers? Apparently they're both old enough to need a cover. But what's remarkable about 15 is how interesting contemporary pop music sounds -- even in the mouths of a children's chorus. The Pussycat Dolls are atrocious in any format, but the Chris Brown and Estelle covers sound great, as does Jason Mraz's "I'm Yours." (We heard a rumor that Lil Wayne's "Lollipop" was going to be on here, but it didn't make the cut.) We're converts.