I spent a couple years on a Java Swing project and hated every minute. Karsten Lentzsch provided the only saving grace with the JGoodies libraries and seesaw supports the JGoodies Forms.
I just started writing some Clojure in my free time and I hadn't looked into GUI toolkits yet, but this definitely provides a great jump start. Bringing enlive's selector style to Swing widgets will make life livable again.
I think if you have to work with Swing, you definitely have to go with the Netbeans Swing GUI Builder. I have worked in some Swing projects and it has been a joy to use. It comes out of the box with the IDE.
Among other things, Seesaw 1.3 will hopefully have friendlier support for pulling in UIs laid out with UI builders (NetBeans, the Google one in Eclipse, etc).
With some custom code and the help of libraries like MacWidgets, you can make some decent native-looking GUI's with Swing. See my profile for an example of one - it's a large-scale desktop application.
I concede though that if you go with out of the box LNF's, even Nimbus, your results will not be up to par.
Why not wrap Clojure on top of SWT? The native look and feel would look better. And if the interactive and incremental nature of Clojure can be weaved in, it would be fantastic for UI development.
Oh good! Closure's been on my To Learn periphery, and I wondered if Monkeybars could be adapted for it, or if the general ideas (e.g. decoupling concerns; using dynamic look-up to drive compiled GUI classes so a WYSIWYG editor can be used) could be employed.
I just started writing some Clojure in my free time and I hadn't looked into GUI toolkits yet, but this definitely provides a great jump start. Bringing enlive's selector style to Swing widgets will make life livable again.