The international launch articles I read had some pertinent info:
Currently, the factory can make about 180,000 iPads a week, while Apple has been selling 200,000/week in the US since the national launch (though they had some already made, as production started a few weeks before). With the international launch we'll see the orders go up, but apparently some supply line improvements mean that next week the factory will be able to build 250,000/week. How much of a backlog we see now will depend on how high demand is elsewhere, and how much US demand has tapered off. The remainder of the international launch is scheduled for July. so demand will bump up again.