SQL Server 2008 Includes Data Collector
In SQL Server 2008, Microsoft has included an entire infrastructure devoted to collecting and reporting on data to improve decision making capabilities.
The Data Collector is a system that can collect data from any TSQL query like DMVs, Windows Performance Counters, and the SQL Trace. It bundles any selection of these items into a Collection Set. This data is then stored in a relational database known as the management data warehouse.
Microsoft provides three bundled collectors, however you can create custom data collectors via T-SQL and there is an API available.
Check out a screencast about the new data collector in SQL Server 2008 via MSN Video below, or if you prefer YouTube or download.