All web frameworks which do not support automatic updating of all content during development shall hereafter be referred to as "Legacy Web Frameworks". Is your shop using them?
Justin Voss and I have been hard at work on a web micro-framework called Ratpack (inspired by Ruby's Sinatra). Lest it become a Legacy Web Framework right out of the gate, we've implemented basic auto-reloading right away. Feel free to grab this for other uses, as it works independently.
groovy runapp.groovy app/myapp.groovy app
The script app/myapp.groovy will be killed and re-run when any content in the app directory changes.
Since Ratpack uses Jetty, there are probably better solutions. Feedback is welcome.
The NIO.2 Filesystem in JDK7 will make this sort of thing much easier.