We use it for Coding systems at Work. No malware/viruses to speak of and it works fine.
If all you do is browser, email and Office stuff, you are safer with Linux. If you are coding Java/Groovy/Grails type stuff, you are better off with Linux.
Windows is a very baggy system.
Linux is just about the buggiest thing out there. I run a real machine and several VM's under various flavors of Linux and there are kernel and lib patches to Linux far more often than Windows; in addition to which there is nowhere near the array of hardware nor the level or sophistication of software supported by Windows. Software development environments -- which is what I do for a living -- under Linux are a complete joke.
Linux is fine for very limited uses. It isn't appropriate for consumers at all, no matter how little ability or need they may have.