The interactive Scala shell console works now, with 'up'/'down' key for command history.
And as ant based Scala project, the project building just works fine, in the building output window, you can click on the compiler error message to jump to the corresponding location of source file.
You may have also noticed, if an id is used as operator, it's highlighting in special color.
The case clauses are listed in the outline window.
Click on the picture to enlarge it
Read: Scala for Netbeans Screenshot: Scala Console and File Locator for Compile Errors