Currently I'm watching talk where they are building an app with Flex, JSF, and WPF (Silverlight?) The speaker is developing live on stage. This seems dangerous, but it is going quite well. It is barely tapping the potential of Flex, but is very convincing. An interesting comment was that Flash is limited because it cannot do any 3D. Of course this comment is coming from a NVDIA engineer, but it is a valid point.
It is very nice to have so many non-Java related talks at JavaOne. The content of JavaOne has really aligned well with the interests of the attendees. I think next year it will be even more so. I predict that next year the dynamic languages will take over and command the biggest audiences.