I've had a good old thunk* about the matters raised in this thread, which mostly relate to getting a suss on the people behind the personae (check out Avy's Impersonet bit); and I've come to an interesting conclusion.

A Board where people operate under pseudonyms and are not obliged to reveal any more about themselves than they wish is a bit like a masquerade. But this isn't a masquerade in the negative sense of a sham, I think. The ability to enter a new community free of past associations and preconceptions can actually be tremedously liberating. In some ways, it gives participants the chance to be more themselves than may have been possible for some time.

It's possible that among the aforementioned limiting preconceptions (and yes, it has to be said that these have often been accepted rather than imposed) are those that relate to a person's sex. In the context of a Board, even these preconceptions can be avoided - without recourse to elaborate disguises! This may be important to some people.

IMHO this has the potential to end up a bit like a Shakespearian comedy (although those are restricted to women playing men I believe), but there's no harm in that. There is, however, a lot of entertainment value in the fundamental mystery, the gradual revelation, and even the odd faux-pas if handled with sensitivity and (above all) a sense of humour!

*thunk (n): like a THINK, but deeper