SAP has announced the full General Availability and Unrestricted Support for SQL 2008 R2 as of 16th September 2010.
SQL 2008 R2 offers some significant benefits for SAP customers. It’s highly recommended for customers with large systems or Unicode systems to move to SQL 2008 R2. This allows to take full advantage of SQL’s new features like Unicode compression or support for 256 CPU cores.
More details on this topic you can find in this article:
Running SAP Applications on SQL Server
Other useful information about Tier-1 applications running on Microsoft SQL Server and the Microsoft Windows platform you can find on newly created blog, written by folks from Microsoft who work closely with ISVs.
Topics of interest include discussions of best practices, webcasts, white papers, performance results and case studies.
Enterprise Applications on Microsoft SQL Server