If you're a Windows guy don't go to college with something new just go with what you know and focus on whats important the computer isn't one of those things.
Why not learn both? The more skills one has makes one more valuable. Or so the theory goes. And the only real differences are ones a person will never use, since the applications and fundamental theories behind design, programming, baking a pie, whatever, don't change between platforms because of a branding logo.
I was an exclusively Windows guy until going back to college, when I picked up a MacBook Pro since some of the instructors indicated that some shops are Mac-only, and I knew the lower-end Macs were much slower (coming from Windows, which uses the same Intel hardware and knowing what it's capable of...) The applications that run on Mac and Windows are 99% identical in most cases, though the Windows version of
certain Adobe applications were far more stable. Performancewise neither OS had a big advantage. On certain details, OS X was better and for others Windows has it. Neither terribly impacted what I was learning in college, but learning both platforms gave me a lot more insight into each's strengths and weaknesses.
It honestly didn't take long to learn how to use OS X and make backups of data. Keystroke shortcuts and the new location of close/minimize/maximize buttons were simple. If it took long to learn an OS designed for "ease of use" then the word "embarrassing" comes to mind. Where and how to save data or school files was identical.
Plus, lots of students asked various questions on both platforms. Again, with registry issues, there are reasons OS X is better. and on the flip side, I think Windows handles preemptive multitasking smoother... like rendering 3D in a couple applications I use, I can load a game and have no ill effects in Windows. In Mac OS X, same Mac hardware, the same conditions cause stuttering. So it's better just to go for a walk and let the computer have 100% of the processor time for the rendering task...
Now if people are going from Mac or Windows to, say, a portable Commodore 64 or Timex ZX81 or anything running CP/M and have to learn a CLI... Or Unix/Linux prior to the creation of "X Window System" (and even then, LOL), then I agree. But windowing operating systems came about because people did not want the complexity of command line interfaces.