That has very little to do with developer-friendliness... The ability to run my development OS in a virtual machine, preferably on a hyper-visor, is paramount.

That has very little to do with developer-friendliness... The ability to run my development OS in a virtual machine, preferably on a hyper-visor, is paramount. Am I supposed to buy one physical machine per configuration that I want to test? Apple has recently gotten a little friendlier in this regard. At least now you can run OS X in a virtual machine at all, even if it does have to be on Mac hardware. Microsoft also has a history of private APIs. Not really...and especially not on the level that Apple does. (Can you name some off the top of your head that are not security related?) It's not just about APIs either. It's usually an utter lack of functionality on Apple's part. For example, look at Finder vs Explorer. Does Finder have an official/supported plug-in architecture yet? Why not? Power users and developers have been begging for this for over ten years. What do you suppose Apple's reason is for only allowing the Dock program to affect NSScreen visibleFrame? I believe that it's the same reason that Apple took forever to allow people to resize Windows by all sides. It's the same reason that they never admitted that a single-button mouse is not better - they think they know better than any other developers out there. That's unfriendly. Fortunately, you can use Java or any mixture of widely-used open source libraries, which are often far easier to compile and use, given that OS X is a fairly regular UNIX. Apple is not very inviting to a large portion of developers, yet there's (sometimes) an alternative, so that means Apple is friendly to developers? I know that all of the *nix devs out there are on Macs now because Linux failed miserably as a desktop OS...but that still doesn't make Apple friendly to developers. There's a reason that Apple has this bad reputation with developers, particularly in comparison with Microsoft. Part of it has to do with their business model, part of it is simply hubris and in any case, there's a long history to consult here.