I have some good news for you — Jay Freeman, aka saurik has just updated WinterBoard with support for iOS 7 and iPhone 5s’ 64-bit processor.
While WinterBoard 0.9.3912 adds support for iOS 7, saurik notes that Wallpapers are not supported:
Wallpaper (whether png, html, or any of the other crazy formats that I should never have added to WinterBoard) is not currently supported on iOS 7 :(.
Please be patient: there is a lot to fix.Along with the compatibility fixes, the WinterBoard icon has also been redesigned, in line with the iOS 7 flat design language:
