Secret to Apple iPad profits
Not 300,000 sold

Okay, so Apple's iPad sold 300,000 units its first day, netting Apple about $180-million if my calculations of 300,000 times $600 is correct.

The secret of Apple's iPad is in the upsell, though. In its first day, there were 1-million iPad apps downloaded. Let's figure that at $1 per app. Not bad for upsell. Also not reported were all the iTunes downloaded. Probably a few more million dollars. A quarter of a million books sold to the iPad. At $10 per book, you do the math.

The iPad appears to be an add-on, or upsell, dynamo.