Just read a great article where AARP replaced an Oracle implementation with IBM Netezza.
AARP had been using Oracle Database for their data warehouse. But their system simply could not keep up with the demand. As Margherita Bruni from AARP says, our analysts would run a report, then go for coffee or for lunch, and, maybe if they were lucky, by 5:00 p.m. they would get the responseit was unacceptablethe system was so busy writing the new daily data that it didnt give any importance to the read operations performed by users. The stresses on their system were so great that in 2009 alone, their Oracle Database environment had more than 30 system failures. To compound matters, these system performance issues meant that full backups were not possible. Instead AARP would back up only a few critical tables, which is a less than desirable disaster recovery scenario. Clearly, something had to be done.