Sorry for double, but i think it’s important for Blender users, so as a bump/notify:
I’ve just installed Blender 2.74 back, and now it exports correctly, without the extra Armature object. So with Blender 2.75 there is a problem with exporting skeletal meshes, but with 2.74 it’s ok. If you have problems, revert back to 2.74.
@Kblargh, when you check it with 2.74, make sure you actually open your project with 2.74, because windows explorer might still point to 2.75 .exe of Blender (if you have multiple Blender versions on your machine). In my case, going back to 2.74 worked.