Quote Originally Posted by junx
/cast [target=party1target, exists, dead] Skinning

You have to update the macro when your skinning skill advances.

So it becomes:

/cast [target=party1target, exists, dead] Skinning(Expert)
/cast [target=party1target, exists, dead] Skinning(Artisan)
I don't think you need to update the macro. My Skinning is almost up to 300 and I am still using "/cast Skinning".