The Office 2010 Beta has been available for a short while now and should be released sometime next year. I’m already quite attached to it, and not only because of the “People Pane” in Outlook 2010 and its coming ties to various social networks.
To help with the coming migration, some new Office compatibility tools have been released. See http://blogs.technet.com/gray_knowlton/archive/2009/12/04/office-2010-application-compatibility-tools-beta-now-available.aspx for more details.
Also, if you aren’t yet running the Key Management Service (KMS) or using Multiple Activation Keys (MAK) with Windows Vista or Windows 7, you’ll probably want to study up on Volume Activation, as Office 2010 will use it too. There’s also a new beta version of the Volume Activation Management Tool (VAMT) 2.0 available for download here.
12/10/2009 Addendum: There is another new download that might be useful at http://www.microsoft.com/downloads/details.aspx?FamilyID=600c2142-abc3-4fea-9271-0c326c45dc8f&displaylang=en. It’s a poster that describes the deployment and installation options for Office 2010.