Here's a revision of my paper on how Rush Rhees' remarks about animals point to a kind of animal ethic which is neither speciesist nor--in the typical ways--anti-speciesist. (Indeed, I suggest Rhees' ideas can help bring out the confusion of both speciesism and the theoretical assumptions of typical anti-speciesist frameworks.) Quite a bit has changed, for the better I hope! Comments always appreciated.
UPDATE (7.29.10): I added a reference (on p. 19) to Elizabeth Anderson's excellent article, "Animal Rights and the Value of Nonhuman Life," in Sunstein and Nussbaum's (2004) collection, Animal Rights: Current Debates and New Directions. (I highly recommend this essay.)
Update 6/9/11: A more recent draft is here; the paper is now forthcoming in Philosophical Investigations (and I will have to take down this draft when the paper is published).
(previous draft removed)