The opinions expressed herein are my own personal opinions and do not represent my employer's view in anyway.
For those of you that already have some experience with the SQL Server 2005 or even SQL Server 2000, and would like to learn the new features introduced in the latest version of SQL Server, a good place to start would be the free Microsoft e-Learning Clinics of SQL Server 2008:
Besides SQL Server 2008 Clinics, Microsoft is also offering the Introducing Microsoft SQL Server 2008 eBook written by Peter DeBetta, with seven chapters dedicated to the new features, including security, administration and performance:
Chapter 1: Security and Administration Chapter 2: Performance Chapter 3: Type System Chapter 4: Programmability Chapter 5: Storage Chapter 6: Enhancements for High Availability Chapter 7: Business Intelligence Enhancements
Download the eBook: http://csna01.libredigital.com/?urss1q2we6
You can practice in about thirteen SQL Server 2008 virtual labs available at Microsoft web site: