I just noticed on the netbeans-dev mailing list that Caoyuan Deng’s plugin support for Scala in NetBeans has been granted one of the “innovator grants”. This is good news! You can already download (very) early versions of the plugin, and there is a mailing list to provide feedback. A proposal describing the intentions for the plugin is also available. The grant challenge ends in August.
Also, I’ve been checking up on the public code repository for the IntelliJ Scala plugin and there is continued work there as well–although last I heard, the team isn’t promising anything just yet (e.g. it’s a matter of resources). It appears to target the next release, IntelliJ IDEA 8, instead of the current one.