I agree with needing more data but I will give my testimonial. I switched from Windows 7 to Mac Lion several months go and have not looked back. Simple things like responsiveness of the touch pad, gestures, and a better terminal are definitely what got me. Overall I would say the UX is just simply better.
OSX has definite advantages here. 1. The trackpad hardware is great. It's so good that when we were making the Bamboo Touch at Wacom, the Macbook Pro trackpad was the standard we measured ourselves against. 2. True pixel-level scrolling from HID devices. Windows has the concept of "wheel scrolling", but it's only vertical, and lots of apps won't scroll in less than a wheel increment (which is oddly 120 units), so you…
I used Mac for a week and went back to Windows. The jerky scrolling in Windows was driving me crazy. The fact was that before Mac I never realized that (maybe I'm numb to perfection) but it was only using Mac that it occurred how much crap scrolling is in Windows.