The user specifies what pronouns to use, and perhaps there would be default values (or you could fill them all in by selecting a "traditional" option). I actually really like this idea. Users would be able to hide their gender if they wanted, and if they wanted to use something like "he or she/him or her/his or her" or "ey/ey/eir", they would be able to just fill it in, and the system would use it in its automatically generated notifications and stuff (Alex posted a comment on eir webzone). This would give us an easy way to gain exposure and experience to the various attempts at creating gender-neutral singular third-person pronouns, and maybe figure out which ones are good (or whether it's worth bothering about).

Also, it might allow for funsies like this.

  Possessive: His Majesty's
  Subjective: His [random from: Awesomeness, Sleepiness, Whimsy]