There are two new hotfixes to add Windows Vista SP2 and Server 2008 SP2 to the supported platform list for ConfigMgr 2007. The first is for ConfigMgr SP1:
The second one is for ConfigMgr RTM, if you haven’t yet moved to SP1 (better hurry up, SP2 is due out soon):
As with the previous fixes (http://blogs.technet.com/mniehaus/archive/2009/06/12/configmgr-hotfixes-available-to-support-windows-vista-sp2-and-server-2008-sp2-os-deployment.aspx) the changes are already present in the ConfigMgr SP2 beta.
And if you are really behind and still running SMS 2003 SP3, they’ve added SP2 to the supported platform list there too: