Comment Re:Java vs. Flash (Score 3, Informative) 520
Check out Processing http://processing.org and Laszlo http://openlaszlo.org for some 'early' options. Processing is still scripting/programming based and outputs Java applets but is a decent start to a Flash alternative using Java. Laszlo is an XML + Javascript language for creating web applications that currently outputs to swf. There has been talk about publishing to Java and DotNet. Laszlo also has an IDE plug-in for Eclipse.
While neither Processing or Laszlo are nowhere near as easy to use for designers as Flash is - they are a start. Problem is programmers are required to make the ide tools for non-programmers to use.