Note: These are rough notes from the WWW2007 conference.
There are lots of different widget technologies. Content is getting more modular. The W3C is working on the Widget Recommendation. Right now there is bad fragmentation with widgets specs.
In the future, Web applications will be built out of proprietary formats like Microsoft’s Silverlight and Adobe Apollo. Vendors aren’t coming to the table to do this type of standardization.
There is work on Web APIs. They are codifying XMLHttpRequest. They are working on a Clipboard API, FileUpload, DOM3 Events, Selectors APIs, and a Network API.