I forgot to put the <sarcasm> </sarcasm> tags in.

I'm not sure that's the issue as much as the fact that Apple offers very
little Enterprise support.  It's sort of a catch 22- Enterprise customers
don't use Apple because of the limited support, and Apple offers little
support because Enterprise customers don't use Apple products...

And they're correct, it does.  If users could cut over to OSX entirely,
and if IT had staff capable of supporting OSX already, then it might not
be as substantial an investment.

In the real world, despite having a large number of OSX fans in my
circle of friends, each and every one has Windows installed, either
using parallels or bootcamp.  There are various reasons, but ultimately
it comes down to one or more mission critical applications require
Windows.

The result is that those users have 100% of the security and
administration issues of Windows, plus the various OSX issues to handle.
Oh, and they not only pay a premium for Apple hardware, but still have
to purchase a second OS too -- This substantially increases the
acquisition costs.

Now that OSX has enough of a market share to sneeze at, malware authors
are starting to notice it exists, and make no mistake, the vast majority
of zombied Windows boxes out there had their zombie installed by the
user, in the form of a trojan hose delivery system.  No operating system
which allows user installable programs is invulnerable to a user willing
to unwittingly grant root level access to malware.

If you're a Microsoft shop, you likely don't have anyone in IT capable
of supporting the OSX platform, which means you need to either train
staff, or hire staff.  Since in a parallels installation, both operating
systems have access to each other, you really *need* someone competanent
to manage both.

Depending on your environment, OSX may not be a bad choice, but it costs
more to support additional platforms -- This is just as true if your
default position is OSX, and suddenly you have a Windows junkie who
insists on sticking with their platform of choice -- This post isn't to
dump on OSX, it's simply a representation of the facts of life being a
significant underdog.