I was reading an article in Information Management by Shaku Atre about "The Value of In-Memory Analytics" that could be an advertisement for Kognitio's Pablo product (http://www.kognitio.com/pablo).  The advantages that Atre lists are:

1. Speed

2. Flexibility

3. Cost Savings

4. Reduction in IT Maintenance

Atre makes the case that "in-memory analytics makes building indexes and cubes unnecessary".  Of course, there are a lot of tools like Excel Pivot Tables that allow a user to access cube structures, so even if we are using in-memory technology, being able to present data in a cube type view to a user allows the user to continue using their existing tools.  This is exactly what Pablo does.  You define your cube meta data but the cubes are never really populated.  Instead, "because we are accessing the data electronically in-memory, there is no need to have aggregations. In RAM, one has the luxury of doing entire table scans in a blink."

You can read the full article here: http://www.information-management.com/infodirect/2011_199/hard_drive_in-memory_analytics-10020180-1.html