First off, I believe you meant Macintosh as a whole platform, not the iMac alone. I also note that you focus on the Commodore 64 and totally ignore the millions of Apple II series PCs that stayed on the market until roughly 1992 which was its primary competitor. I'll admit I don't know the total number myself, but I'm quite aware that the Apple II spent quite a few years in the educational market before the iMac came along to supplant it. Now, I'll accept and acknowledge that iOS devices are selling more quickly than their OS X devices, but that doesn't make the Mac expendable since Apple has seen steady high growth of Mac sales as well--to the detriment of PC sales over the last 5 years.