Although they look native, the iCloud preference panes — on iOS and OSX — are actually web views. You can test this yourself on an iOS 6 device: iCloud settings will show iOS 7 icons for some apps.
In regard to the iconography itself, I like it. It is reminiscent of the iPod ads from way back, with fluorescent silhouettes.[ It is a nice spin on the stereotypical iOS 7 icon theme of using a white mask on a gradient. In comparison to the current set of texture-rich, these icons evoke a much more playful (and casual) tone. The old ones look too serious.