Released today are the conjugal Arms of Their Royal Highnesses The Duke and Duchess of Cambridge, which were approved in February this year by Her Majesty The Queen. Conjugal Arms are those that show the separate shields of a husband and wife, side by side. In this case, the two Shields are the Duke's on the left and the Duchess's on the right with both supported by the Duke of Cambridge's Supporters of the Royal Lion and Unicorn, which is made to look different from The Queen's by adding his white label of three points around their necks with the central point charged with a red escallop shell taken from the Duke of Cambridge's mother's Arms of Spencer.
For the full heraldic story, stretching back to the announcement of the engagement between Prince William of Wales and Miss Catherine Middleton, see here.