Few of the features that i know

1.SQL Server 2008 R2 will have editions that support up to 256 logical processors, an increase from the maximum support of 64 logical processors with past releases.

2.Master Data Services(MDS) part of BI solutions, people say it is introduced avoid data conflicts in DW, not sure how to implement it.

3.One more new feature in BI is Power Pivot, PowerPivot is designed to meet the more focused BI needs of end users through integration with Microsoft Excel and SharePoint.

4.SQL Server Reporting Services (SSRS): adds to previous geospatial data types by offering new visualization mapping capabilities for reports.

5.SQL Server Management Studio (SSMS): new dashboards to DBAs for monitoring and managing multiple instances of SQL Servers from a single screen, this functionality is not available in SQL Server express edition.