Pages could have a linktitle (perhaps via meta), and
wikilinks could use that title by default when linking
to the page. That would allow pages to have a simple, easily linkable name
(without spaces, for instance), but use the proper title for links. For
example, Directive could use the linktitle
"preprocessor directive", and pages for users could have linktitles
that put spaces in their names.
Ideally, perhaps two versions of the title could exist, one for general
use, and an optional one for if the case in the actual link starts with an
uppercase letter. That would allow directive to
use the link text "preprocessor directive", but
Directive to use the link text "Preprocessor
Directive", for use at the beginnings of sentences. If the second version
did not exist, the first version would apply to both cases. However, that
also seems like potential overkill, and less important than the basic
functionality of linktitle. --JoshTriplett