Canonical interwiki prefixes

It is time to establish some canonical interwiki prefixes that will become the standard for those wikis that wish to accept them. As functionalities such as those offered by Extension:InterwikiMap for mass adoption of standardized interwiki maps becomes more widely used, it will be beneficial to avoid unnecessary disparities between the interwiki prefixes in the maps used by various sites.

Most of them should be pretty uncontroversial. But the technical question arises, given that there are so many wikis, how does one pick the best interwiki prefixes? It would be impracticable to individually contact all 20,000 wiki owners to ask what their preferences are and then manually process the responses. Here are some ideas:


 * Use the prefixes available from interwiki map for those wikis that are listed there.
 * In general, a balance needs to be struck between picking an interwiki prefix that's short enough to be convenient to use, but long enough to avoid ambiguity and conflicts with other prefixes. Keep interwiki links to at least four characters.
 * Generally go with the URL over the official name of the wiki, because it's likely to be shorter but not too short. If it's a URL like examplewiki.examplehost.com, only use the first segment (viz. examplewiki) if it makes sense to do so.
 * Begin migrating toward a system in which wiki owners volunteer their preferred interwiki prefixes. This could be done via directories such as Wikiindex. Or maybe it could be made a configuration setting that could be retrieved through siprop=general.
 * Sort out collisions manually, with regard for such factors as who owns a trademark to a name; who has the official URL (e.g. examplewiki.com would take precedence over examplewiki.examplehost.com in most cases); which wiki was established first; which wiki asked for the interwiki prefix first; and size, popularity, wikifactor and other measures of importance of the wikis.
 * Strip out spaces, colons , ampersands (&), and equal signs (=).
 * Avoid conflicts with languages (e.g. en:).
 * Watch out for interwiki prefixes that might collide with mainspace articles. E.g., a wiki prefix Commandos: would collide with Commandos: Behind Enemy Lines. Prefixes that have the word "wiki" in them should be okay.