Actually, I am sure. Since MacOS X is based and is UNIX, it makes it very simple to see what software is running on the computer. Also the software would require a local root exploit (which is very,very,very,very rare on BSD systems) to install spyware on it. Windows is built for advertisers to flood you with ads, MacOS X makes it very simple to prevent them -- I never see banner ads on the internet or popups without having to buy special software or use a third party browser.