Bottom line = SP1 does not yet provide support for any role running on Windows Server 2008. Read on . . .
The Supported Configurations Guide included with SP1 RTM (ProductDocumentation folder) states the following:
Windows Server 2008 Operating System
Detailed support for The Windows Server 2008 operating system will be published 90 days after the release of Windows Server 2008. This document will be updated on the System Center Operations Manager TechCenter Web site at http://go.microsoft.com/fwlink/?LinkId=90676.
For additional information on Opsmgr07 Role support as well as MOM 2005 support see http://blogs.technet.com/momteam/archive/2008/01/09/support-plans-for-opsmgr-2007-sce-and-mom-2005-running-on-windows-server-2008.aspx
Also applied to SCE SP1