Cupertino proactively addressed the supply shortage expected after the Japanese earthquake by divesting to other suppliers, and eating up the manufacturing costs increase by prepaying for the touch panels.
This is reported to be one reason that the BlackBerry PlayBook launch is delayed. RIM's tablet was supposed to become widely available on April 19th for $499, but this will probably be pushed with a month. We will be at RIM's PlayBook event next week in New York, so we'll know if that's indeed true.
Apple has reportedly shelled out $3.9 billion in larger touch panel supply deals, which is the company's traditional way to secure priority shipments and discounts. Plus, Apple can afford it, with its $50 billion war chest.