Hello, Nathan!
This is a great question!
When you're on the Disney Dining Plan, you receive entitlements for each person on your resort reservation for each
night of your stay. As such, if you were traveling alone, on a five night stay, on the traditional Disney Dining Plan, you would have five Quick-Service entitlements, five Table-Service entitlements and five snacks to use however you'd like from the moment you check in and receive your Key to the World card until midnight after check-out. In 2012, you'll also receive a resort-refillable mug, details of which are available on your particular plan. In addition, the number of entitlements is placed into one account for all parties traveling on the same reservation; this will help you to keep track of the balance of entitlements your party has not yet used (it's printed on your receipt.)
I've included a link to Walt Disney World's Disney Dining Plans here for you, in case you haven't had a chance to look over them.
What's also great about this year's Dining Plan is that all of the Downtown Disney restaurants are now participating in the plan. You could easily never step foot in a park and find plenty of wonderful restaurants from which to choose throughout the resorts and Downtown Disney as well. We often plan on enjoying a meal at our resort on a lazy pool day as well as a meal at Downtown Disney on our day of check-out.
Please send us any additional questions you may have as you plan a trip to Walt Disney World! We love to help!