PowerPivot announced today.
My quick note:
What it is: In memory DB that runs on server or client to allow users to sift through massive amounts or data -- 100 Million Rows in Excel distributed as SQL Server Power Pivot for Excel and SQL Server Power Pivot for SharePoint
UPDATE: Right after my laptop's battery died I saw a demo of Sorting, Filtering, and Grouping on millions of items all of which took parts of a second.