ESRI has released a sample JavaScript viewer example with a developer’s guide to help you better understand how the JavaScript API works. ?It looks great (much like the Flex API) and does a darn good job having cross platform compatibility. ?As I said the Developer’s Guide is a great resource for those looking for an introduction to the JavaScript API, Dojo, Aptana Sudio, and what it takes to develop ArcGIS Server JavaScript applications.?