Windows 7 is in many ways based on the same kernel as Vista, but they have various global problems and given it a make-over. With Snow Leopard is the reverse case. There is incredibly little visual difference to upgrade from Leopard to Snow Leopard, but they have a whole infrastructure upgrading and optimizing it. Basalt however, they have the same mission. They will develop their operating system, not put all the rails on. Read Detailed Review : Snow Leopard vs. Windows 7
I'm still finding comparing the two a bit fallacious. 1) If you're using a Mac, you're using OSX by default. If you need to run Windows, you can run it side by side on the Mac, along with OSX. 2) If you're running a PC, you can't run OSX on it. So, for me, it's not really comparing Snow Leopard vs Windows 7, but more of Snow Leopard + Mac vs Windows 7 + Whatever PC Rig. And it's not like you can Upgrade Vista to Snow Leopard or Vice Versa.
I have been a Win users for over 20 years, but I'm now on Mac as I'm a Linux fan but I wanted the nice UI that Mac or Win has, plus the Unix OS. I upgraded all our computers to Win 7 within this last month. While it's an improvement in processing it looks about the same, but still is slower than Mac OSX. Nothing is Virus free, and Macs can get Trojans all day long.
To be clear, Macs are not based on Linux at all but a custom combination of FreeBSD and Mach. It is a certified Unix OS, though. Despite the contests for expert crackers and forum postings, you would find it extremely unlikely to ever get one.
It's easier than ever to pit Windows 7 and OS X 10.6 Snow Leopard head-to-head: They're launching soon, both within a month of each other—and both are basically glorified service packs of the current OS. In way, they're opposites: Windows 7 uses the same core foundation as Vista while fixing issues and prettying up the outside, while Snow Leopard keeps most of the same spots while re-arranging how things work internally. But the mission is the same—to evolve their current OS—not change the whole game. And launching this fall, we can't avoid a comparison study. The stars of Redmond and Cupertino have never been so closely aligned before.