Kudos to Alexander and Ilya - here is an interesting blog article that talks about the recent release of IntelliJ IDEA CE, and how its Scala plugin is the hidden gem:
"Right now, IntelliJ has the best Scala support. It has more features and less bugs than NetBeans, and it is much more stable than Eclipse. Scala support is one of the features supported in the community edition. That means a lot of newbie Scala developers can just use IntelliJ. This is great news. I would not give NetBeans or Eclipse to Scala newbies, for the simple reason that both of them report syntax errors inconsistently."