When Microsoft first disclosed its plans for "Kilimanjaro" (SQL Server 2008 R2), officials also made mention of a related project, codenamed "Madison."
On May 11, Microsoft announced a first Community Technology Preview (CTP) for Madison is now slated for July.
(I couldn't get the SQL Server 2008 R2 guys to provide a date as to when they are planning to release the CTP of the next version of SQL Server -- beyond "very early in Q3" -- but my bet is that's on for July, also. Microsoft seems to be syncing up the CTPs for the next version of Office and SQL Server, given the dependencies between some of the associated technologies, like Master Data Services.)
Madison is expected to be Microsoft's entree into the data-warehouse appliance market. It is based on technology Microsoft acquired when it bought DATAllegro in July 2008.
From a May 11 posting to the Microsoft Data Platform Insider blog:
"The SQL Server Data Warehouse Product Unit plans to release MTP1 - the first Madison Technology Preview - in early July. A select group of customers will deploy a prototype MPP data warehouse on SQL Server 2008."
Microsoft has not provided a final ship-date target for Madison. Company officials have said they expect to ship SQL Server 2008 R2 in first half of 2010.