Baker expects that Lion will do well, but cautioned that even in the best circumstances, revenue generated by the upgrade will be "just a footnote" to its total income.
Apple may be taking an unprecedented sales step with its desktop operating system, but the company's not only following an existing trend but will be tailed by others, including Microsoft, said Baker.
"There's no [retail] upgrade cycle for tablets or smartphones," Baker observed, adding that Lion's use of the Mac App Store is just an extension of those models.
"And it's clear that Microsoft will on some level go to an app store in Windows 8," Baker continued. "The question is whether their app store is a controlled environment, or whether they'll work with their OEM and channel partners. I think there will always be ways for retailers and OEMs to participate in software sales. Microsoft is fundamentally a good channel partner."
While Microsoft showed some parts of Windows 8 on June 2, it has said nothing about integrating an application store in the new operating system. Earlier, however, several Windows bloggers reported finding signs of one in leaked previews of the OS.
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