Monster sales for iPad on launch day?

In a report to clients issued Saturday night, Munster’s estimated that by midnight Sunday, Apple will have sold 600,000 to 700,000 iPads, including pre-orders — more than double his relatively conservative pre-launch estimate of 200,000 to 300,000. (Other analysts had published estimates of 300,000 to 400,000.)

By comparison, Apple reportedly took 74 days to sell one million iPhone when the gadget first debuted. The iPhone 3G and Phone 3GS each took just three days to sell the first million units.