http://www.colorado.edu/its/oneonone/oneononespring08.pdf
Includes:
"Some might be surprised that Apple OS X is mentioned in the previous
paragraph. Ever since the Month of Apple Bugs (January, 2007
www.securityfocus.com/brief/397) many in the security community have
predicted that we would see increased attacks against Apple’s OS X
operating system. For the entirety of 2007, we did not track a single
incident of spyware for OS X. In general, most OS X incidents involved
weak passwords allowing an attacker
Network Security Enhancements and Apple Surprises
by Dan Jones
Dan Jones is the director of campus IT security at CU-Boulder.in via
SSH or other remote access. Unfortunately we are now seeing a definite
increase in successful attacks against OS X involving spyware. In
fact, OS X currently accounts for 39% of spyware incidents."