If you are upgrading from BDD 2007 (any version) to MDT 2008, the instructions are covered in the "Getting Started Guide" included with MDT 2008.  So I won't repeat that discussion here.  I want to focus on the new scenario, upgrading from the original Microsoft Deployment to the new Microsoft Deployment Toolkit 2008.  Here are the basic steps:

  1. Make sure you have a backup of your environment.  While I don't expect anything to go wrong, it's always a good practice to have a backup :-)
  2. Install the new MSI.  This will automatically upgrade the existing installation files, e.g. C:\Program Files\Microsoft Deployment Toolkit.
  3. Run the new Deployment Workbench.
  4. Click on the "Distribution Share" node and run the "Create Distribution Share" wizard to upgrade the scripts and tools in the distribution share directory.  You can choose to backup the existing scripts as part of this.(After doing this, you may need to press F5 to refresh the nodes under the distribution share node.)
  5. Update (not files only, as you need to get the new scripts into the Windows PE images) each deployment point.

MDT 2008 does not require Windows AIK 1.1 if you are using only Windows Vista RTM, Windows XP, or Windows Server 2003; Windows AIK 1.0 is fine for these.  But if you are using Windows Vista SP1 or Windows Server 2008, you need to upgrade to Windows AIK 1.1.  (If you don't, as soon as you add a Windows Vista SP1 or Windows Server 2008 image, you'll start seeing warning dialogs.  They won't go away until you do upgrade.)  The steps needed to upgrade to Windows AIK 1.1 are:

  1. Uninstall Windows AIK 1.0.
  2. Reboot.
  3. Install Windows AIK 1.1.
  4. Run Deployment Workbench.
  5. Update (not files only) each deployment point in order to get the updated Windows PE 2.1 images.  (Windows AIK 1.1 includes Windows PE 2.1; Windows AIK 1.0 included Windows PE 2.0.)

That should do it.  Now you're ready to start with Windows Vista SP1 and Windows Server 2008 :-)