I found an interesting paper on the Microsoft downloads web site with a detailed summary of the Microsoft Silverlight Release history. You can download and read it from here.

Here is a brief summary:

• Build 3.0.40818.0 Released September 1, 2009
• Build 3.0.40723.0 Released July 27, 2009
• Build 3.0.40624.00 Released July 9, 2009
• Build 2.0.40115.00 Released February 18, 2009
• Build 2.0.31005.00 Released October 14, 2008
• Build 1.0.30715.00 Released July 23, 2008
• Build 1.0.30401.00 Released April 4, 2008
• Build 1.0.30109.00 Released Jan. 15, 2008
• Build 1.0.21115.00 Released Nov. 20, 2007
• Build 1.0.20816.00 Released Sept. 4, 2007

Microsoft published the RTM bits for the Silverlight™ Tools for Visual Studio 2008 SP1. This package is an add-on for Visual Studio 2008 SP1 to provide tooling for Microsoft Silverlight 2.

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Microsoft released the first Release Candidate of the Silverlight Tools for Visual Studio 2008 with SP1. Click here to read more.

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