> disabled people

Writ broadly. Last time I looked into who was editing Wikipedia on my own academic discipline, it was several people who had an obsessive autistic fixation on the subject, but whose autism was apparently so socially debilitating they couldn't gain employment, not even in academia with its somewhat greater accommodation for oddballs. The upside is that they could channel their interest productively into WP. The downside of this is as outsiders to a field where much consensus is found only at real-life conferences and lecture handouts, their info was often years behind the state of the art (and, of course, WP demands that citations be to secondary sources, even if obsolete).

On the bright side, as encyclopedias go that's much more up to date than my parents' World Book from the 1960s or even my CD of Encarta 1996.