A while ago I posted a blog on Reporting on SAP data with Microsoft tools and have an update regarding SQL Server 2008.
Integration Services for SQL Server 2008 supports the extract of data from or the export of data to SAP BI InfoProviders such as InfoCubes, Data Store Objects (DSO), and InfoObjects. Unfortunately you can only use this method if the SAP system has Open Hub Services activated, otherwise you will need to use a solution such as ERP Link.
Microsoft have released a technical white paper entitled: Using SQL Server 2008 Integration Services with SAP BI 7.0 detailing common scenarios for likely usage and how to's.
You can find out more by reading the white paper which is available here:
http://msdn.microsoft.com/en-us/library/dd299430.aspx