One of the key areas for the SQL Server 2008 release is to be a scalable Data Warehousing platform. Many organisations have deployed it – with DW ranging from 1TB well into the 60-80TB.

So what makes SQL Server 2008 Enterprise a better choice than SQL Server 2005 is due to the star join and few-outer-row optimisations. A recently released whitepaper goes into further details and also has some test results on IBM servers.

Link: http://msdn.microsoft.com/en-us/library/ee410012.aspx