I made the switch to the Mac platform a number of years ago when it was the only way left to upgrade my machine. I'd begun on a DOS-only 286, graduated to a 486 and a Pentium and to Windows 3.1, Windows 95, and Windows 98, and I'd built my last PC from components. My daughter still uses (and prefers) that machine, which I upgrade for her once a year. I've replaced processor and motherboard many times. She's using Windows XP Home, and though I haven't kept up my Windows under-the-hood smarts, I've got a pretty good sense of the difference for a user.
I will never go back to a PC, even though the Windows platform is keeping up nicely with the Mac's functionality and all the heavy-duty graphic apps (starting with Photoshop) now have excellent Windows versions. I know of only one Mac application that seriously trails its Windows sibling, but it may be an important one to you: it's Quicken.
The matter of the Mac's freedom from viruses is, as has been pointed out, subject to the psychological obsessions of those malignant souls with nothing better to do than cause trouble for strangers. The Mac's smaller market share makes it less of an attention-getting stage for them. Apple's success with the iTunes Store and iPod could trigger their psychosis any day.
But as I was setting up my daughter's PC in her college apartment last week, it froze and refused to start Windows for a while. After a few puzzled moments, I got it to reboot correctly, but what struck me was my daughter's blase response. To her, computers freeze every now and then. After several years using Mac OS 8, 9, and now X, I just shake my head in disbelief.
Once a user becomes accustomed to an interface, they tend to defend it vigorously and to denounce the other platform -- which ought to tell you they don't call it an interface for nothing. You do become engaged with it. But functionally the interfaces are so similar it's a snap to switch from one to the other and you'll wonder what all the disagreement is over; about all you have to remember is that the buttons at the top of any window are reversed, and when you close a Windows window you also close the program, freeing up RAM. When you close a window in OS X, that's all you've done -- the application is still residing in memory.
Aesthetically, it's another story for me. I find Apple's designers to be among the best in any industry, and looking at the Apple interface is pleasurable for me to the same degree that using utilities to tinker with Windows used to be. The difference is that now I don't spend time working on the computer's own software to make it run better (which provided a very satisfying feeling); I spend it getting things done.
New Macs are equipped with Boot Camp, which will allow you to run your Windows applications when you need to. Boot Camp must be looking good; Microsoft has dropped Virtual PC, the heretofore Windows-emulation app of choice. I used Virtual PC when I made the switch. You just get Mac versions whenever you would normally upgrade, so you don't have to run out and buy all new apps at once.
You'll find an amazing shareware and freeware community online. And though there are many more PC applications available, you'll be able to find everything you need.
Take advantage of educational rates for software while you're a student, particularly with programs that allow you to upgrade later (some don't).
I think you'll just feel better and better about having made the switch. And the best part is, those smug Apple users won't bug you any more, because you'll know what they're all grinning about...
Oh, one last thing: when my wife's work was burglarized a few years ago and some laptops were stolen, a laptop was fenced through a pawnshop in another state and the buyer tried to register it. Apple Customer Care notified the police. Pretty good customer service.