Actually... I wonder if the iDevices are still a gateway... but not to Macs. Perhaps Apple wants to get as many out there as possible because the real money is in the content they allow Apple to sell? In this scenario, as long as Mac owners account for a good portion of the content sold, then Macs will continue to be available. Just a thought...
Content is the gateway product. The real money is in the iPhone :
If anything, iPad is a gateway product to iPhone. Content is the gateway to all of it. Macs are a side business.
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You mean back when Apple didn't have a "portable" product line, two app stores, and a media store? Even if licensing out the OS did kill off PC sales, Apple would still make a huge amount of money. It won't come close to killing the company like last time.
Sure, but it would kill 13% of its revenue... to gain what exactly ? Support nightmare ? Complexification of OS X ? I really doubt selling a bunch of OS X licenses to Lenovo, Dell, Asus can get them 1-2 billion $ per quarter like the Macs do.