SQL Server 2008 Service Pack 2 CTP is avaible now.
New Features in SQL 2008 SP2 CTP
SQL Server Utility
Data-tier Applications
Reporting Services in SharePoint Integrated Mode
SharePoint Integration
Collaboration and Reuse
Data Sources
Data Visualization
Report Layout and Processing
Aggregates, Expressions, and Functions
Report Authoring Tools
Cache Refresh Plans
Report Manager Enhancements
Business Intelligence Development Studio
New Web Service Endpoint
New Report Definition Language Schema
New Sp2 CTP applies on
SQL Server 2008 Enterprise Edition
SQL Server 2008 Evaluation Edition
SQL Server 2008 Developer Edition
SQL Server 2008 Standard Edition
SQL Server 2008 Web Edition
SQL Server 2008 Express Edition
SQL Server 2008 Workgroup Edition
System Requirements
Supported Operating Systems: Windows 7; Windows Server 2003; Windows Server 2008; Windows Server 2008 R2; Windows Vista
32-bit systems (x86)
PC with Intel or compatible Pentium III 600 MHz or higher processor (1 GHz or faster recommended)
64-bit systems (x64, ia64)
1GHz or faster processor
Minimum of 512 MB of RAM (1 GB or more recommended)
675 MB of available hard disk space
Download
SQL Server 2008 SP2 CTP
Reference:
What's New in SQL Server 2008 R2