Small market share. Currently 8% used to be 4% which greatly reduces the chances of spyware and viruses.. But as the market grows for Mac, that will change dramatically vs 90% of market for Windows..
The argument that OS X has less viruses is true, but that is against XP, BUT Mac OS X has viruses, a friend of mine has a virused Mac. As more users use Macs, more viruses will come out for it. Especially when users think "they are safe".
Mac OS X was hacked in 2006 under 30 minutes, and hacked within 2 minutes in a contest in 2008. Linux and Vista were not able to be hacked until another day when restrictions were lowered.
All macs are standardized with Cameras, if your system gets hacked, the hacker would more likely be able to turn on your camera.
Please Note: All OS's have vulnerabilities.
LINUX ADVANTAGES:
1) Install Linux, and then get tons of stuff for free. Updates done, etc.. Linux is very easy and has tons of software that will be updated automatically. (Checking a checkbox in either two ways to install (Add/Remove or Synaptic Package Manager), search for something I want, check a box and click apply)
2) If you like the effects on a Macintosh go yahoo or google COMPIZ FUSION. It can do just about any cool effect a Mac can do and more...
3) If you like the Dock on OS X (Mac) google/yahoo Cairo Dock, avant window navigator.
4) Linux is MORE SECURE. I surf the internet and can even run some windows programs on Linux.
LINUX OS
If you are worried about viruses, spyware, security, Try Linux (it is free), I have included some information about Linux and links so you are not lost if you decide to try it.
Easily turn your system into a Dual booting computer with Linux, fast, safe and secure, easy to use (contrary to belief). You then get the best of both worlds (Windows with all of its supported products, freely go online without the worry)
Macintosh's are far from bug free. Sample of problems: Overheating Macbooks, OS X- not responding to keyboard, some units with 16bit screens, etc. Apple statistics are misleading since Mac users with problem machines are more likely to go out and buy a new computer than PC users. Apple is lowering prices which means you can expect lower quality than in the past. Apple had switched the manufacturers producing parts. OS X also has problems slowing down.
http://www.tuaw.com/2008/08/01/apples-quality-dwindling-my-macbook-pro-sob-story/
http://news.softpedia.com/news/Microsoft-Finds-Irony-in-Mac-OS-X-Getting-Hacked-Before-Vista-SP1-82135.shtml
http://www.ubuntu.com/
http://www.kubuntu.org/
http://www.freespire.org/
http://www.pclinuxos.com/
http://distrowatch.com/
http://polishlinux.org/
http://www.desktoplinux.com/
http://xwinman.org/gnome.php
http://xwinman.org/kde.php
http://www.linuxalt.com/
http://screencasts.ubuntu.com/
http://www.linuxfoundation.org/en/OpenPrinting/
http://www.avast.com/
http://www.free-av.com/
http://www.personalfirewall.comodo.com/
https://help.ubuntu.com/community/SwitchingToUbuntu/FromMacOSX
https://help.ubuntu.com/community/SwitchingToUbuntu/FromWindows
Google/Yahoo OS X on PC