This is all interesting. IMHO, the only reason Windows is exploited more is because it is hated more.
I'd put it the other way around, I'd say those do the exploiting *love* the fact it's so insecure.
As MacOS X gains market, vulns will be found and exploited because everyone wants to unseat the king of the hill, again this is my opinion only
I'd agree more attempts will be made on the more popular systems but that in itself does not mean it is less secure.
I think it is something of a myth that Windows is considered insecure because it has the biggest market share.
Apache has the biggest market share for webservers but does it have as many vulnerabilities as IIS? No.
Someone mentioned that BSD is just a kernel...
Linux is technically a kernel though most people use the term to refer to the entire OS, BSD is an Operating System (actually a family of them).
MacOS X (not sure about the current Panther/Tiger) was all FreeBSD with a lot of new utils and a pretty GUI put on top... the utils are indeed what separates "Darwin" from FreeBSD, but you can run most of the same commands at the prompt and it is still FreeBSD under the hood. That having been said, the same exploits that may be in FreeBSD (not secured) will be present in OSX.
Not quite...
OS X includes a chunk of FreeBSD in the kernel along with MACH along with a load of stuff from FreeBSD, OpenBSD, GNU etc. on top.
That having been said, the same exploits that may be in FreeBSD (not secured) will be present in OSX.
Assuming the part in question is present and hasn't been changed.
Anyhow, all platforms have potential to be exploited.
That I agree with 100%