Which is amusing as some of the most die hard OSX/iOS lovers/developers I've known have always said they hate XCode and if they could use VS they would swap in a heartbeat.

Yes, they are both great and I can't say I hate one or another, but only that I like them both
The only thing that made me disappointed on VS2010, the last time I used it, was its heaviness. By that I mean it was packing my projects with lots of MB of intellisense and slowing things a bit.
I am really impressed by XCode 4 because it has lots of features and my project still is light and still runs smoothly.
People I know tend to get angry with XCode because it has lots of features hidden in its menus making it hard to find sometimes and on some updates Apple tends to change their places. That is bad, but I can get used to it really quickly.

Other thing that I like in XCode a lot is the tool for testing and profiling.
VS2010 introduced much better tools for profiling as well, but I didn't get to test them deeply. XCode ones are very intuitive to use.

As an artist, let me throw in my two cents (even though it will be similar to what has already been stated)

Mac OS had been "faster" at rendering high resolution graphic and art work because of the ways the data bus worked on their processors/memory vs PC. It was "cleaner" in the overhead and background running processes vs the graphic heavy UI of Windows. Over the years Microsoft and hardware vendors have vastly improved in leaps and bounds and severely closed those loopholes closing the gap between the two. Photoshop CS on Windows is going to net the same results as Photoshop CS on MacOS now. There are arguments that Mac still has more efficient 64bit processing than Windows, but what you see on your end isnt that stark of a difference. As an IT professional by trade, the argument MacOS has no virus/vulnerability is false because no one who write malicious code bothers with Mac as much as Windows, simply because 80% or better of the global user base is Windows. Should it be reversed, you would hear "Windows never gets viruses" if 80% used MacOS.

I do tend to do alot of my 3d assets, art, textures, etc in Mac simply because that is what I learned and used in school and my software (Maya, Photoshop, Nuke, etc) are MacOS version. But, for game work, I have and use both systems. With modern Intel based infrastructure in modern Macs now, there is no reason not to use either a parallels or bootcamp dual boot solution. That is what I do. Boot into MacOSX for art and 3d, then boot over into Windows for my Visual Studio/XNA work along with UDK dev work.

One point that might also be worth considering is that for people that need serious hardware grunt, Apple haven't really kept their Mac Pro line up to date.

With so much of their profit coming from iOS, it seems unlikely that Apple will focus on it's image as a tool for creative professionals.

Why am I not surprised folks are comparing hardware ( which is irrelevant ) instead of the OS.
Since it's a Hardware War ....

"" My TI99 is better than your Atari 800 ""[/quote]

Back on subject - for me, the Apple OS was quite clunky "back in the day" ( System 6.x ), with MS-DOS being a much better choice to get things done.
I discovered Windows 2, and was hooked on the GUI interface. MAC still was clunky 6.x at that point.

Along came Windows 3, and System 7.x . Windows 3 offered more of what I wanted, and I stuck with that. At this point in time, Linux was just getting started, and was stuck back in the early 1980's style of computing. ( I tried it once )

Fast forward to today. Windows still offers more software options and compatibility than MACs do. ( WINE sucks ). I have so many tech toys that are just unavailable to MACs.
From what I have seen over the years, MAC has alienated it's self a lot in the software market, and continues to be irrelevant for what I want to do.
I haven't forgotten about Linux. It's upgraded to the late 1980's computing style now.

I use Windows for almost everything.
MACs I only use when I have a compatibility issue.
Linux I only use when it is absolutely necessary - mostly when others can't figure out how to use it.

I've never had any experience with OS X that has ever given me the impression that it is any easier to use or less crash-prone than Windows. That stupid spinning beach ball ruined more than a few hours of work in the animation lab back in the day. As for the hardware, I was just talking with a friend on Facebook about it and the best summary I could come up with was "brushed aluminum, herp derp".