Earlier today iTunes allowed customers to signup in Canada, Europe, and the U.K; however, after signing up, customers were unable to use the service.
Apple has since begun refunding customers who were billed for service. Beau Giles, a MacRumors forum member, posted his refund email which can be seen below.
The email reads:
I apologize for this Beau but as of the moment, iTunes Match is only available to Brazil and United States. iTunes Match will not function if the customer's account is not a United States or Brazil account. I have reversed the charge for "iTunes Match". In five to seven business days, a credit of $34.99 should be posted to the credit card that appears on the receipt for that purchase.