For many years Mac owners have been talking about how safe their computers are because they didn't suffer the problems Windows owners had.
Those days are slowly changing because the growing popularity of Apple and their share of the market is now making them worth the effort of some computer hackers.
The first piece of malicious code to specifically target Apple computers was detected last year and the number of malicious programs has increased by a very large amount the past several months, with over 100 variants the past couple of months.
Apple computers now have about 10 percent of the consumer computer market and sales are expected to be tremendous during the Christmas shopping season.
Here are some links to articles that contain more details:
Apple's rising popularity attracts hackers - Financial Times - MSNBC.com
Hackers target Apple Macs as popularity rises - Telegraph
» F-Secure: More than 100-150 malware variants targeting Macs | Hardware 2.0 | ZDNet.com