Just another technology to watch:
http://titaniumapp.com/


Titanium is the first open platform for building rich desktop applications.

* Open source
Titanium is licensed under the Apache Public License (version 2)
* Open web
Use standard HTML, CSS and Javascript to build rich desktop apps
* Open desktop
Run your apps on Windows, Mac and Linux (coming soon!)
* Open API
Add rich desktop capabilities to your apps using a simple Javascript API