MilkShape or CharacterFX or... or...
Fragmotion.
This and Character Fx support weights (good for organic joint deformation) while Milkshape 3d hasn't. I need to guess if ms3d format supports it at least; then the python blender script could export it and we'r saved sooner or later
BTW, tools for importing a texture mesh and animating are a bunch: in mid cost or low cost or free you mean, yup, gmax(md5 export only), blender, 3d canvas, gamespace(a bit pricy imho compared to the others and results) , messiah, hash, etc. Maya,lw,max(ms3d export, too),xsi(ms3d export also, I think) export directly as x, obj.
An x loader would be great, but is a load of work. Mnemonic is working hard on the tools, so I think definitely the way we should aim to is discover how to export weights animation from blender in ms3d format. I'll dig about that one.