For now, the best way to get involved is by downloading the source, building it, and playing with it. Participate in the forums, etc..
Building is pretty easy. The only prerequisites are that ANT is installed/setup and that you have the Log4j jar file in your classpath. This can be done simply by placing the jar file into the meta-jb/dev/lib directory of your source checkout.
Some packages are built conditionally based on certain external jar files being present. See the dependencies page for details. These jar files can simply be placed in the meta-jb/dev/lib directory as mentioned above.