I see fuzzy boundaries between the various categories. Anyone doing 3D must necessarily work in 2D at least for textures. One can't do much in animation without working in 3D generally. Suggesting limitations to 3D in the title might not be wise. While there's a lot to animiation, I don't see it standing alone as its own SO style site. Too many participants have expertise overlapping the various areas and won't want to be logging on to several sites every day. Lump it all together and use tags.
Proposal: 3D Graphics, Modeling & Applications