PRO: Designing and Optimizing Data Access by Using Microsoft SQL Server 2005

Design client libraries to write applications that administer a SQL Server service.

• Design server management objects (SMO) applications.
• Design replication management objects (RMO) applications.
• Design automation management objects (AMO) applications.
• Design SQL Server Networking Interface (SNI) for asynchronous queries.

Here's MSDN's section on SMO.  Darshan Singh has an overview of SMO at YukonXML.com.  David Hayden has an example of how to create a table using SMO.

MSDN's section on RMO.  There is not a lot of community activity in respects to RMO.  Here's my take.  Probably good to know how to create a publication (EnabledTransPublishing on ReplicationDatabase, Create a TransPublication object), create a subscription (TransPullSubscription, or TransSubscription), how to cause a syncronization (TransSynchronizationAgent).  Keep in mind I've never use these objects, these are the ones that strike me as important.

It appears that AMO really means Analysis Management Objects.  There appears to be no reference anywhere to "automation management objects" anywhere.  Here's MSDN's section on AMO.  Liu Tang and Paul Bradley wrote a overview for MSDN magazine.

SNI For Async?  It looks like SNI is used for tracing.  Here's an article at MSDN that mentions SNI.

Next up-> MARS