Exchange 2007 SP1 on Windows Server 2003 or Windows Server 2008?

After spending some time thinking about the question regarding whether you should deploy Exchange 2007 SP1 on Windows Server 2003 or Windows Server 2008, I decided to do some more research on it. 

I came up with the table below and I am including the public sources of my information as well.  In short, using Windows 2008 could provide a faster migration experience as well as performance improvements.  I am actually preferring Windows 2008 now.  Hopefully this will help you in your decision. 

Windows 2008 Windows 2003
+ Faster installation time – No additional downloads or prerequisites required. Additional components can be installed using an XML file. + Familiarity of Windows 2003 – less learning time
+ Already Running Windows 2008 and no need to upgrade at a later date.  + Already a stable base OS for many customers
+ Performance and scalability enhancements for Client Access server - This requires installation of a number of additional hotfixes and Service Packs to get Exchange 2007 SP1 installed
+ Multiple subnet failover clusters – support for SCC or CCR in multiple Datacenters without the need for a VLAN to span subnets - CCR requirement for same subnet restricts options. SCR can be done across different subnets however.
+ More Quorum configuration options for clustering. - There is no supported upgrade path from a Windows Server 2003 running Exchange 2007 to Windows Server 2008
- Existing Exchange 2003 servers can’t use Windows 2008 domain controllers that are read only.  
- Exchange 2003 may not install correctly in a pure Windows Server 2008 forest if you try to install Exchange in a child domain without installing Exchange in the parent domain.
- The big unknowns – The “Wait until SP1 rule” that many have.  

This is not by any means a complete list of all of the benefits of going to Windows 2008.  This is only what I have found publicly so far as Exchange 2007 SP1 goes.  As I spend more and more time with Windows 2008 I am really liking it.  I like the new interface for managing roles and features a lot. 

Sources of material: