Tibco Silver Spotfire

I am just now getting to look at Tibco Silver Spotfire business intelligence and visualization package.  It is now available as a one year free trial.  A clever marketing ploy I think, especially with regard to the length of trial.  I plan to compare it to Tableau Software package, often mentioned here,  in the coming month. In the past I have used both packages, in the enterprise and out, but more recently have primarily used Tableau.