There are over 14,000,000 OSX Macs.... and four years that OSX has been in use.
There were far fewer OS9 and under users before OSX became available... and yet those hackers found Mac attractive then. There were at least 12 Mac viruses that came out in the last two years of the old operating system. So, now we have 14m Mac users and four years and the PSX virus count is still ZERO.
Why the sudden loss of hacker interest?
There has been ONE Trojan observed in the wild (a file claiming to be a pirated copy of MS Word for Mac) that trashed someone's user files because HE installed it... and one or two proofs of concept that did not have a vector AND to be effective required the user to be operating in ROOT, something that less than 1% of Mac users would do .
You should also note that UNIX is found in many servers... a target that is well worthy of any hackers efforts. More and more xServers are being installed and they are Unix AND OSX... again a good target that can hit all computers in the server's area of service.
There has been a large cash prize offered for any hacker who could compromise the UNIX security. I heard the prize was dropped because of lack of applicants. Those who tried, failed.
Those who program enterprise apps with UNIX state that while it IS theoretically possible to design a UNIX/OSX virus, the degree of difficulty is a NINE on a scale of one to ten where ONE is the degree of difficulty for writing a Windows virus.
You have to either approve loading or frequent lots of porn site to get infected IMO.
Actually, I don't think you get too many infections from porn sites... it does happen but for the most part, they are businesses who don't want to piss off their potential customers. The REAL culprits are on-line game sites. ALmost every time I have found a client's PC heavily infested with Malware its because some kid visited an on-line game site...
A friend just finished a computer forensics class (geared towards law enforcement and investigation applications) and utilized the knowledge thus gleaned to have a look at his hard drive at home (Wintel system). Said he was taken aback by the amount of garbage on his system, and can only attribute it to the gaming sites he's visited.
So yeah, I can second your observation, in a second hand kind of way.