Looking at some more options for setting up hardware environment for AX2009, I came to know about the virtualization option using Windows Server 2008 R2. This is really a good way to consolidate the various server roles (in other words machines) onto a single physical machine. Using the Hyper-V technology, we can now have the AOS, Batch Server, Terminal Server on a single machine, however the DB should still be installed on a separate machine at least for Production environment.
Another important thing to remember about Hyper-V is it needs 64-bit processor (either Intel or AMD) and 64-bit version of Windows Server 2008. A general confusion is that one can also use 32-bit version with Hyper-V and this is not true. You may have 32-bit OS as guest OS on virtual machine running inside Hyper-V.
I am looking at more details about this topic particularly by setting up a virtual environment for AX2009 in test environment and will share my experience with all of you.