I just checked out the 10 minute intro to Laszlo and it was pretty interesting.

It’s an XML user interface language, similar to XUL. You write
JavaScript event handlers like XUL. You can make your own tags like with XBL, except the Laszlo syntax seemed more intuitive.
I didn’t see any mention of CSS for styling though. The Laszlo stuff gets compiled into a Flash movie so you can have cute animations and it works in any browser that has a Flash player.

This 10 minute demo walks you through the basics. I liked in particular
the XML data binding and the drag & drop features.

If you have a few minutes to spare, it’s a fun little interactive demo.

Thanks, Andrew!