[antimora]

Sounds like a lot like Wicket (component based web ui). And honestly, I don't like this idea for the web. Web UI is not desktop UI. Make make both of them equivalent, one requires adding a special layer that converts API calls to HTML rendering, which can make things unnecessarily slow (as it was slow in Wicket, and it's also slow in Muntjac).

[mbell]

It depends heavily on how its implemented. I use primefaces[0] for java development and find it amazingly easy to build data based sites quickly, its also very fast. It uses jQuery UI for many components so it is very easy to extend / modify.

[0] http://www.primefaces.org