I'm constantly wow'ed by how Apple and OS X just manages to nail the user interface so perfectly almost 100% of the time. People who bash Apple products... have you ever used a Mac before? The user interface is incredibly refined. Everything feels slick and the operating system prioritizes the UI to make sure you don't feel as many slowdowns. The trackpad on the Unibody MacBooks are simply amazing. I've never used a better trackpad in my life, and the multitouch and gesture implementation are beyond anything that Windows computers have. Even if the functions are the same, things just feel smoother.
There are also nice little touches to the OS X system that a lot of people don't know about. For example, if you switch your keyboard from QWERTY to Dvorak, you can still maintain your Cntrl/Command C/V copy/paste shortcuts whereas Windows has no such provision. Audio output is superior to any PC that doesn't have at least mid-high end audio equipment. The screen on the MacBook or Apple Cinema displays are also nice, bright, contrasty and only recently with RGB-LED's do we see any other manufacturers affordable displays start to beat Apples.
Yet at the same time, Apple manages to screw up so many basic usability quirks as well. The program utility bar for example is at the top of the screen... which is great, until you install a 2nd screen. The utility bar always stays on the main screen, so if you have a program open in the left monitor, the bar is still on the right monitor. USB ports are seriously lacking on the MacBook Pro line and putting every single port on one side of the computer just plain sucks. I've had power, video, 1 Firewire and 2 USB devices plugged into my laptop and there's just no room for 5 cables sticking out of the left of the computer. And of course there's Apples draconian policies regarding their "i" devices, iPods, iPhones, iTunes, etc. It's really a nightmare compared to open systems.
So that's my rant of the day. I'm currently going through this ADHD phase with my love/hate relationship with OS X. Apple's tight control of both hardware and software really allows them to nail down the user interface in a way that Windows and it's 5000 hardware partners couldn't hope to accomplish.
Still, I think that for the vast majority of home computer users, OS X provides a better experience overall. Even Windows 7's interface doesn't feel as slick or as fast.
Oh and let's not forget Linux! I use Ubuntu sometimes too and believe that it would suit the needs of most people if not for hardware compatibility and software availability issues.
Oh yeah... I guess the question is, do you use Apple's OS X or Microsoft Windows? Why? Or do you just not care and use whatever computer your family gave you for college?