Keep up with your ressie confirmation numbers...take them with you to all meals. We usually have a good many reservations, and once in each of the last two trips, disney-dining has messed up one. Not too bad, considering, but mistakes are made. In '03, they booked DW and DD7 (a mom/daughter princess breakfast) two months early, on Aug 1st instead of Oct 1st. We only caught it due to those being held with a $10 deposit each, and we saw a $20 charge to our cc statement. We called and a dining-manager 'forced' in a new reservation for a totally booked Oct 1st. But we had to go directly to the restaurant to remove the $20 charge.
This trip, we had Monday LTT ressies, and they couldn't find them. We gave them the number and it listed us for Thursday. They gave us a table quickly, though, even though they were booked.
Having the reservation number really helps, vs. just giving them your name. In future trips, we'll call to confirm as well. Have fun!!