The main reason viruses aren't a problem for Linux is it's not really a usable system.
And the main reason they aren't a problem for Mac's is hardly anybody owns a Mac.
How often to maladjusted egomaniacs attack the little guy? Oh, sure, they go after the occasional windmill but only because they think they are a giant.
Not that I'm all that happy with MS but for years they've had games and programs that run on their system.
22,000,000 Mac OS X users. That's "hardly anybody?"
Usable for what? When I install Linux, it comes with choices of several browsers, a full-featured office suite (word processor, spreadsheet, presentation, and project management), sophisticated graphics manipulation and management programs, money management programs, web, ftp, and dns servers if I want them, tools to allow me to efficiently find, filter, and manipulate data, a choice of full-featured databases, a choice of email clients, web authoring software, development IDEs, multiple desktops, choices of window managers, and more. What do you get with MS-Windows? Notepad, IE, Outlook Express, solitaire? WooHoo!
And the main reason they aren't a problem for Mac's is hardly anybody owns a Mac.
How often to maladjusted egomaniacs attack the little guy? Oh, sure, they go after the occasional windmill but only because they think they are a giant.
Both of the above FUD points are well dealt with HERE.
Not that I'm all that happy with MS but for years they've had games and programs that run on their system.
See above for programs that run on the system.
I don't know of anyone who is "happy with MS" and their spyware/worm/virus magnet. OTOH, I know many satisfied Linux and Mac users who are happy to be able to just use their computers, without having to worry about what today's virus may happen to be.
Don't really know where you've been, but I use Linux daily, and so do a majority of my associates and clients. One of my clients has a call center staff of over fifty employees that operates in a 100% Linux environment. Linux is quite usable.