Glad you're looking forward to your cruise you'll enjoy!
Carnival’s VIP Check-In is an exclusive service. Even though you have those cool luggage tags you must ask for “VIP Check-In†upon arrival at the cruise terminal. Embarkation staff will ensure that you are expedited through the check-in procedure as quickly as is possible, while providing quality service.
You'll also have access to Priority Debarkation via a debarkation letter [delivered to your stateroom evening before debarkation] offering a choice of how to disembark the ship. You will be given the option of Self Assist (where offered) or Priority Debarkation; for Priority Debarkation, you will receive special luggage tags letting you debark the ship after the Self Assist guests but before the remainder of the guests.
We've cruised with Carnival a few times, from many ports and looking forward to Magic's US Inaugural from Galveston 11/14.
Hope this helps!