As per my GSoC project ([[mw:Separating skins from core MediaWiki]]), let's move all four core skins to separate repositories and include them in the tarball. I'm filing this bug to track some dependencies and to have a place to discuss this.
CologneBlue and Modern have been already split to separate repositories, I am in the process of splitting off Vector and MonoBook.
Version: 1.24rc
Severity: enhancement