I hereby contend that the current state of the Mac and Windows platforms is very, VERY different from the state of the OS/2 and Windows platforms at that time.
There is really no comparing the two situations. Doing so sounds good at first glance but this situation is not that one. The similarities one might note are all affected by the pile of differences.
Some examples: Mac OS X has an established consumer user base with significant public mindshare, developer support, and history. (You think too few people know about the Mac... go out on the street and ask random passersby if they ever heard of OS/2

It is also, across the board, fully mature, complete for a huge range of tasks, and in fact often a more productive environment than Windows. And it's tied to some great hardware. And it's not marketed in the way OS/2 was, nor to the same people. And Windows is currently in a situation to be vulnerable to defectors, more than the reverse. And Mac OS has highly polished end-to-end experience that Windows apps break. And Mac OS has a passionate user base that WILL resist non-native apps. (Look at the heated objections people had to running even Classic Mac apps instead of carbon ports!) And the Mac has a huge library of top-shelf, heavily-relied-upon, big-name, profitable native apps already long established.
The list could go on, but bottom line: OS/2 tells us very little about the future of Mac OS. OS/2 was vulnerable in ways that just don't make sense with the Mac platform.
(O/T but I'm reminded of people saying that Apple will lose the marketshare lead with iPod because they lost the marketshare lead with the Mac... when they never HAD a lead with the Mac

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