Which NetBeans projects files should go into source control?

The NetBeans knowledge base article on project files & version control discusses the NetBeans project files, with loose advice about which files are project specific (i.e. can be shared via version control), and which are user specific.

Here is the section on version control:

If the project is checked out of a version control system, the build (or nbbuild), dist (or nbdist), and the nbproject/private folders should not be checked into that version control system.

If the project is under the CVS, Subversion, or Mercurial version control systems, the appropriate “ignore” files are created or updated for these directories when the project is imported.

Though nbproject/private should be ignored, nbproject should be checked into the version control system. nbproject contains project metadata that enables other users to open the project in NetBeans without having to import the project first.