In the US, Asia-Pacific (AP), Latin America and Carribean (LAC) and Canada, its actually 20 days:
Purchase - Centrally processed multiple Merchant Outlets
1
1In the U.S. Region, includes the following Merchant types: transportation companies subject to federal or foreign regulations, oil companies, Car Rental Companies, Hotels, motels, restaurant chains, and other Merchant categories specified by the Board.
Processing Date must be within 20 calendar days3 from the Transaction Date
3 Transaction Date = Check-out or prepayment date
Source:
http://usa.visa.com/merchants/mercha...egulations.jsp
I'm guessing there are EU rules as to this as well.