While I'm no Microsoft apologist, when you factor in that Google also yanked services (and they're in direct competition with Microsoft for everything now that they've announced they're building an operating system and very pro open source), and that the ban extended to Iran, Syria, Sudan, etc., it makes it seem more about government intervention. Also the few tech blogs I've read about on this subject and I don't know if these are all interlinked or what say it's a result of Export Administration Regulations, i.e.:
While Cuba is listed as an American "Enemy," it is more to the point about exporting software to "evil" countries and less about Microsoft or the US government specifically targeting Cuba. I have also read rumors that Skype may be following suit too.
Of course it very well may be the other way around as well, it really wouldn't surprise me since Microsoft has used those tactics before, it is just a bit odd that Google would follow suit considering they're directly directly in competition now and I can't imagine them working on anything together.
Interesting as well:
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