This morning at approximately 8 AM EST, Attunity officially announced its new PowerPivot connector series starting with a high-speed Oracle connector. The high-performance connectors enable affordable and optimized software for loading large volumes of data into PowerPivot. A press release detailing the announcement as well as a free trial (in both x86 and x64 builds) of the new Oracle connector can be found at http://www.attunity.com/press_releases.aspx?newsId=1398 .
UPDATE: A great question I received today regarding Attunity's new release was will these high-performance PowerPivot connectors work with traditional SSAS cubes since that is all PowerPivot really is. From my early testing the answer is yes, the connectors work with both traditional SSAS project data sources as well as for PowerPivot data sources. A very nice value-add for processing large data volume cubes.