This document compares features of Microsoft SQL Server 2008 and 2005. Key features of SQL Server 2008 include enhanced database mirroring, automatic recovery of data pages, log stream compression, the resource governor, predictable query performance, data compression, hot add CPU capability, policy-based management, streamlined installation, improved performance data collection, and new date/time data types. SQL Server 2008 aims to provide a more reliable, secure, and scalable database platform compared to previous versions.