Middleton Coat of Arms

The British public has been favoured with the interpretation of Michael Middleton's arms for Catherine:

but what arms were granted to him and in what degree? Will the helm be for a gentleman or for something else; will there be a coronet underneath the helm? Aren't we allowed to know yet? After all, if Catherine is to be made (as rumoured), a Princess of the United Kingdom in her own right and (DV) produce a presumptive heir to the throne, is her father to remain Mr Michael Middleton? Time will tell.