System Center Essentials (SCE) is a “all in one” System Management product, design for small and medium companies. SCE is has a built in limit to monitor 30 servers and 500 clients. The “core” of SCE is built on two products, Windows Server Updates Services 3.0 (WSUS) and System Center Operations manager 2007 (Ops Mgr 2007). SCE will provide patch management, software deployment, inventory and monitoring.
Both Pete Zerger and Björn Axéll has a lot of good information about SCE, you will find links to them under “Links”.