By now, you've already been inundated with the Mac vs. PC ads:
The truth is that I'm not sure that they nail what it is that Mac users enjoy. No doubt all of the iLife, iMovies, iTunes, etc. are great to use. Also, it's no surprise that creative folks love utilizing a Mac. Some of it could be that folks like Adobe and programs like Quark got their start on a Mac.
The element that I believe Apple is missing from these commercials is the elegance of the user interface. Though Windows has evolved and actually mimicked many of Apple's traits, they still have yet to really capture the ease of use.
I'm going to show my age here, but I started in this industry by programming ladder logic in Programmable Logic Controllers (PLCs), moved to DOS, integrated PLCs to DOS, and developed, integrated and implemented applications on Microsoft Windows, IBM OS2 Warp/Warp Server, etc. It's never been simple, but I've always challenged myself at reading and experimenting to automate and integrate more and more. I've got a lot of experience, and you might say I'm a ‘Microsoft Guy', having used it as my primary tool in my jobs my entire career.
OSX (Mac's Operating System), is less cluttered, simple to use, easy to manipulate, customize, integrate, etc. To tell you the truth, one of the funniest moments I had was when I couldn't figure out how to install a program. I didn't realize that I could simply drag it to my Applications folder. Don't you wish it was that simple on Windows? Sheesh.
As for interactivity at work (we're a Microsoft shop), I have had no problems. No problems getting on the network, accessing wireless, utilizing Office and sending and sharing files. It's been quite painless. I do have Parallels running ‘just in case' I need to run XP… but I run it out of a Window on the Mac (it's awesome). There I have Microsoft Access and Microsoft Visio.
So… my first word would have to be iElegance. Apple does a fantastic job at a beautiful, simple interface that runs quite perfect. When I have switched from PC to PC in the past, it's honestly taken more time than it has to switch to the Mac. I'm impressed.