The latest Gartner Magic Quadrant for data warehouse platforms can be viewed here:http://www.gartner.com/technology/media-products/reprints/teradata/vol3/article1/article1.html
Interesting to note the proximity of Greenplum to Netezza in the leaders quadrant, along with IBM, Teradata and Oracle.
Amazing what being bought by EMC can do for a company!
Perhaps most noteworthy is the dash to MPP. It was only a matter of time.
More comments will follow in due course...