WSUS 3.0 SP1 will be available on Windows Update within the next few weeks. The package behavior is:

1. Upgrade all previous versions of WSUS starting with WSUS 2.0 to WSUS 3.0 RTM running on Windows 2003 SP1+
2. All upgrades will require user interaction.
3. This service pack package will supersede WSUS 3.0 RTM packages.
4. Block upgrades of all WSUS installation using remote SQL. This is now a manual upgrade process.
5. Do not support upgrading previous versions of WSUS running on Windows 2008.
6. System Center Essentials 1.0 RTM will not be upgraded to WSUS 3.0 SP1. This will be handled by a future release of System Center Essentials.

Note: “WSUS 2.0 SP1” and “WSUS 2.0 Client SelfUpdate Update for WSUS 2.0 SP1” packages will be expired. These updates are still available on the Download Center.

Source:→ WSUS Product Team Blog

WSUS, Service Pack, SP1, Windows Update