"On the logon script policy, I'm talking about centralized, user or
group-based scripts."OS X Server does logon user and group scripting. You just go to the
Managed preferences for either a user or an entire group, go to the
Logon preference pane, then click on the Scripts tab. They can be
Bash, AppleScript, or any other scripting language you install.
You can also run Apple Remote Desktop Server scripting which works
like ActiveDirectory scripting. You can push out applications, updates,
change preferences, etc. upon logon, logout, upon sync, or any
combination thereof.
"I can tie into AD with LDAP. I can assign permissions based on
LDAP membership on the Windows AD server."So does OS X Server... and then some.
"Although it is amusing that the reason to pick an Apple server is
price, but when you talk about picking a desktop based on price you
get flamed because "you get what you pay for". Which is it?"It's not both ways. The operating system is free on any new Mac, so
the comparison is always the hardware. Apple doesn't make
commodity computers like Dell or HP, so Dell and HP will always be
cheaper.
When it comes to server hardware, the prices are more on par with
each other. Suddenly it's no longer commodity parts thrown together,
even Dell has to do some more-than-average QA testing, pay for
more expensive components that meet stricter fault tolerances, etc.
Since price is not really the object of comparison as the hardware is
concerned, it comes down to the software. OS X Server is free with any
new XServe, so compared to a Windows solution, it's darn cheap.
The price would be more comparable on a Dell or HP running Linux
instead of Windows Server.
"Clustering, Unified Messaging, Voicemail Processing can all be
done from Exchange."Currently UM and Voicemail Processing only work with the iPhone.
Apple doesn't support other phones at the moment, so Exchange does
have the advantage there. OS X Server does support clustering.
"You can custom program forms, setup linked folders in mailboxes
between multiple users, sync offline/online both local mailboxes and
public folder info."Well, technically you could do all of that with OS X Server if you
wanted to take the time. That's the nice thing about UNIX and
working with open source software. Exchange does have the
advantage that it's already setup rather easily. OS X Server takes more
work. I don't know what 10.6 Snow Leopard has to offer in that
regard, though.
"Branch Cache, RPC over SSL, Published Applications and Terminal
Services, etc etc..."Branch Cache seems like an exploit waiting to happen. RPC over SSL
currently available only for Mail and Chat services. According to this
article, it looks like Snow Leopard will extend that. The build in
SSL/TLS can be used to secure almost any communication.
Apple also offers Terminal Services, which are at no additional cost. If
you visit any Apple Store you can experience it first hand. It may not
be as robust as Microsoft's, but it's free. You can also always just use
SSH.

Windows Server requires an additional Terminal license fee for each
person wanting to use Terminal services. User and Device CALs do
not qualify for Terminal services.