Katherine Huberty of Morgan Stanley estimates that one million iPad sales add $0.25 to Apple's earnings per share. I'm lazy, but I am going to claim that a P/E ratio of 20 is "about right" for Apple. (It does bounce around, has been higher, has been lower, and will be affected by the change in generally accepted accounting practices (GAAP). I still like P/E of 20 as an easy number to work with.
One million iPads sold represent a $5 increase in share price. So realistically, in the long term, launch sales represent a $3 increase in share price. Of course, I hope that Apple will sell even more iPads over the long term.
But let's be rational, and not exuberant.
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