Hi Chris,
In version 3.0, no, we still had some parts that relied upon Silverlight. As of version 4.0 Beta 1, though, I believe we've migrated all parts of Esri Maps for SharePoint to JavaScript and no longer rely on the Silverlight framework.
Our 4.0 Beta 2 release should be headed out via the Beta Community shortly...
Katy
Katy Dalton | Technical Consultant
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