Besides Yudkowsky and Goertzel, the only person I know of doing serious computational meta-ethics is Dutch philosopher and computer scientist Gert-Jan Lokhorst. He has a paper forthcoming in Minds and Machines called "Computational Meta-Ethics: Towards the Meta-Ethical Robot." I suspect it wil be of interest to some.
His paper also mentions some work in formal epistemology on computational metaphysics and computational meta-modal logic. Ah, the pleasures of scholarship! (You're all tired of me harping on about scholarship, right?)