DV (Data Visualization) makes more sense when you trying to Visualize huge datasets, which indirectly implies the eventual need for DW (Data Warehouses) and DW appliances (DWA). Among pioneers for DWA we can name the Teradata . This was not a very hot area until 7/6/10, when EMC bought Greenplum with its own MPP architecture. On 9/20/10 IBM bought Netezza for $1.7B and DWA market became officially hot in anticipation of need of DV and BI users for a lot of DWA for their "big data". Teradata claimed 2 years ago that Netezza are far behind performance-wise, but apparently IBM disagrees or does not care... Please note that Netezza, before it was bought, pro-actively partnered with DV vendors, using them as a way to expand their market share and this points us to the future.
With "big data" buzz everywhere, I suspect a large wave of partnerships between DWA (EMC DCA (Data Computing Appliance), IBM, Teradata, Microsoft / DATAlegro, Oracle / Exadata, SAP ( HANA + Sybase IQ ) vendors, as well as vendors of virtual DWAs) and DV vendors is coming in 2011. Data Visualization making DWA much more attractive for end users with huge datasets! Microsoft's PDW was released on 11/9/10 and SAP HANA will be released in November 2010 too