Why did they bother expending resources to go after ISS and SQL Server/MSDE? Why expend resources for OS 9?
As I said before OS X is nearly as good as win 7, so you would have to dupe the users into doing something (like visiting your site). With the extra effort required to attack the hacker is better off on targetting the larger install base.
You posted a worm. It's easy...it exploits a hole in the application and it uses that to replicate itself.
I could post the same to you...were is Windows 7 worm? Since it doesn't exist and it has a larger user base we can surmise Windows 7 is stronger than OSX. Or at least just as good.
You keep bringing up an irrelevant differentiator, trying to recategorize things, in order to keep your flawed theory alive.
Question: Does the Mac have a high-enough population to attract the efforts of malware writers, thus eliminating claims of “security by obscurity”?
Answer: Absolutely yes. Even smaller populations have attracted them.