SQL Server is a complicated animal. IMO, there seems to be two general "areas": administration and application development.

I consider the administration side to cover things like server configuration and tuning, security, backups and recovery - basically things external to a database. I see the application side covering things internal to the database: designing and implementing the schema, creating stored procs and queries, optimizing queries, and designing data access.

Don't get me wrong. In order to be successful, you must have a good overall understanding of SQL Server. It just seems that people tend to gravatate towards one area or another.

-Mike