Lou Agosta wrote a nice article entitled "Getting Started with DW Appliances" http://esj.com/Articles/2009/03/18/Getting-Started-with-DW-Appliances.aspx?Page=1 and I thought I would list it here as this is a good and quick introduction to the topic. Lou gives a quick overview of Data Warehouse Appliances and then talks about how to go about selecting one that is right for you.
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