The goal of automating administration across a large organization is aiming at simplifying the day-to-day job of the DBA and also ease some dataflow tasks between two or more servers.
By definition multiserver administration is administering two or more instances and with it you can do:
- Manage two or more servers
- Schedule information flows between enterprise servers for data warehousing.
Implementing multiserver administration with SQL Server is part of the SQL Centralized Management Solution provided in Codeplex here. Multiserver administration covers the part with Master-Target server of SQL Server Agent Jobs.
Link to the MSDN article on the subject you can find here.