I don't want each language providing its own package manager. Sure, CPAN was a great leap forward back before apt became popular, but now I want to just apt-get install libraries. Language-specific package managers always fall short of apt because they don't deal with external dependencies - cabal isn't going to install the sqlite libraries when I install the bindings, and even if it did, I doubt they're going to take stability and security updates as seriously as Debian does.