Four Pillars of SQL Server 2008 (Katmai)
As you are aware SQL Server 2008 CTP is available for download and the heat is on to catch up what it will be different with SQL 2008 as compared to current evolution of SQL 2005.
SQL Development Team in Microsoft proudly announces that SQL 2008 is built upon the four technology themes, which are Mission Critical Platform, Beyond Relational, Redefining Pervasive Insight and Dynamic Data Development solutions.
There are series of videos available on those 4 pillars, find out them:
MissionCritical video on Enterprise Data Platform Vision
BeyondRational video for new data types and set of services
BI_Vision video within SQL 2008 and integration with Office & Sharepoint systems
DynamicDevelopment video with .NET 3.0 for next gen applicatons