I'd love to see these sites release public documentation to parts of their interfaces so that we could program to those specifications and have some confort that mere whim of reorganization wouldn't leave us with broken links.

cpan:// can't be made to go directly to a module since it has always done searches so we have links like permutations that would get a 404 if we tried to turn that into a direct link.

It'd be nice if search.cpan.org supported a search somewhat like Google's "I feel lucky" where it'd go right to the module/distribution/author if you spelled it exactly right (but a mispelling would do a search rather than leave you at a 404). I personally don't think PM should add a method for direct links to CPAN modules until that happens.