Ever since I heard of the credit, I thought "Cool! iTunes store, here I come - time to pick up another hundred songs!" Then I read the terms and conditions:
Customers may not redeem their store credits: (1) at any iTunes Store in the United States or elsewhere, (2) Apple Store locations outside the United States; (3) at Apple resellers; (4) for cash;
(5) to purchase Apple Gift Cards, or,iTunes Store Gift Certificates, to give iTunes Store content as gifts, or to create iTunes Store allowances; or (6) as payments on Apple accounts.
Sorry, Apple - but THAT blows chunks.