Card Title is a text field associated with every SavvyCard that is generally used to display the name of the company or organization associated with the card if the card uses a stock Background and doesn't have a custom background with the organization's logo incorporated into the header artwork.
Unlike Card Description and Card Name (which are used in mini-cards and email signatures), Card Title is not used anywhere except for the card header. If you wish to edit the name of the Organization or Company displayed in mini-cards / email signatures, you will need to edit the Org. Name field under the Organization Button.