Yesterday we announced a strategic partnership with the Dojo Foundation: OpenLaszlo will not only be licensing the Dojo Toolkit for use within our next major release, we will also make substantial code contributions back to Dojo for use by the entire Ajax/DHTML community.
OpenLaszlo getting into Ajax.
OpenLaszlo is probably set to become the first major tool to develop for them both.
Macromedia have "owned" this area for a while, with Dreamweaver and the Flash tools. The question is how their expensive proprietory software model will compete against OpenLaszlo. Their advantage : good connections with the existing, mainstream web-development community. Their disadvantage, not so good connections with the rest of the developer community. Flash is still weird for programmers.
Microsoft are where? They've turned VB from a decent GUI scripting language into C# with a different syntax, and both are essentially following Java on the road to statically typed oblivion. (With the added disadvantage that these languages are being used to try to drive people onto .NET 2 and Vista)
Java Applets themselves are out of the running. Scripting languages like Python, Perl and Ruby have no real story for GUI development. Tk is from two generations ago. wxWindows is still an awkward amalgum of two third-party libraries. The Java community themselves are deserting Swing for the Eclipse library. So why would, say, a Python programmer choose Jython + Swing? (Although she might, I suppose, choose Jython + Eclipse.)
Mozilla's XUL is intriguing but has no significant support from a development environment.