Check it out. Hot new topic for the Ask the Experts feature over of JSC:
Topic: JRuby Support in NetBeans IDE 6
Experts:

• Tor Norbye, Principal Engineer, Sun Microsystems
• Charles Oliver Nutter, JRuby Core Developer, Sun Microsystems
• Brian Leonard, NetBeans Evangelist, Sun Microsystems

One of the significant new features added to NetBeans IDE 6 is support for JRuby.
With this support, Ruby developers can take advantage of NetBeans IDE
features such as code completion and the debugger to develop and
maintain their Ruby code.

Got a question about the JRuby support in the NetBeanss IDE? Post it
during this session and get answers from three experts: Tor Norbye,
Charles Oliver Nutter, and Brian Leonard.

You have until this Friday to ask your question. So go do it! These guys are great! ;)