When I try to export one of my models with the new fbx 7.4 binary option I get the following error:
Traceback (most recent call last):
File "C:\Program Files\Blender Foundation\Blender\2.71\scripts\addons\io_scene
_fbx\__init__.py", line 415, in execute
return export_fbx_bin.save(self, context, **keywords)
File "C:\Program Files\Blender Foundation\Blender\2.71\scripts\addons\io_scene
_fbx\export_fbx_bin.py", line 2602, in save
ret = save_single(operator, context.scene, filepath, **kwargs_mod)
File "C:\Program Files\Blender Foundation\Blender\2.71\scripts\addons\io_scene
_fbx\export_fbx_bin.py", line 2518, in save_single
scene_data = fbx_data_from_scene(scene, settings)
File "C:\Program Files\Blender Foundation\Blender\2.71\scripts\addons\io_scene
_fbx\export_fbx_bin.py", line 1976, in fbx_data_from_scene
if tex.texture.type not in {'IMAGE'}:
AttributeError: 'NoneType' object has no attribute 'type'
location: <unknown location>:-1
location: <unknown location>:-1
The same model does export with the old 6.1 ASCII export option and the error message is sufficiently vague that I have no idea where to start looking.
What is a ‘nonetype’ object, and why is blender surprised it doesn’t have an attribute ‘type’, which seems obvious from the name? 
(As may be evident, I don’t know any python)