[AnotherUnixGeek]

Much of the change has been generated by MacOSX. People are pleasantly surprised by the fact that it uses Unix under the hood.

These folks should also consider the BSD variants (FreeBSD, NetBSD, OpenBSD, etc.) in addition to Linux. MacOS X is built on FreeBSD.

However, if I had to choose a secure OS, I'd probably go with VMS.

Another excellent choice for a secure OS would be OpenBSD.

[Wonder Warthog]

"MacOS X is built on FreeBSD."

I thought MacOS was built around the Mach kernel???

[Frumious Bandersnatch]

Sort of. I believe that Mac is actually built on the Mach kernel which is a BSD derivant (whether freeBSD, OpenBSD or just plain BSD, I don’t know).