FULL PRODUCT VERSION :
java version "1.8.0_20"
Java(TM) SE Runtime Environment (build 1.8.0_20-b26)
Java HotSpot(TM) 64-Bit Server VM (build 25.20-b23, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Originally reproduced on MS Windows 8 OS, but should be generic for all supported OSes and not specific to only MS Windows OS.

A DESCRIPTION OF THE PROBLEM :
Wrong colors are used for selection foreground (black instead of white) and selection background (light gray instead of dark blue) in JList, when Nimbus L&F is set.
http://stackoverflow.com/questions/25685269/wrong-colors-in-jlist-when-using-nimbus-and-java-8u20

REGRESSION :
Last worked in JDK 8u11.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Compile, run the provided sample application and select any entry in JList.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The default colors should be used for selected entries in JList.
ACTUAL -
Since JDK 8u20 wrong colors are used.

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import javax.swing.DefaultListModel;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import javax.swing.plaf.nimbus.NimbusLookAndFeel;

public class Test {
    public Test() {
        try {
            UIManager.setLookAndFeel(new NimbusLookAndFeel());

            JList<String> l = new JList<>();
            DefaultListModel<String> model = new DefaultListModel<>();
            model.add(0, "sssssssss");
            model.add(1, "sssssssss");
            model.add(2, "sssssssss");
            model.add(3, "sssssssss");
            l.setModel(model);

            JFrame f = new JFrame();
            f.setSize(500, 500);
            f.setLocationRelativeTo(null);
            f.add(l);
            f.pack();
            f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
            f.setVisible(true);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                new Test();
            }
        });
    }
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
final NimbusLookAndFeel laf = new NimbusLookAndFeel();
UIManager.setLookAndFeel(laf);
UIDefaults defaults = laf.getDefaults();
defaults.put("List[Selected].textForeground",
    laf.getDerivedColor("nimbusLightBackground", 0.0f, 0.0f, 0.0f, 0, false));
defaults.put("List[Selected].textBackground",
    laf.getDerivedColor("nimbusSelectionBackground", 0.0f, 0.0f, 0.0f, 0, false));
defaults.put("List[Disabled+Selected].textBackground",
    laf.getDerivedColor("nimbusSelectionBackground", 0.0f, 0.0f, 0.0f, 0, false));
defaults.put("List[Disabled].textForeground",
    laf.getDerivedColor("nimbusDisabledText", 0.0f, 0.0f, 0.0f, 0, false));
defaults.put("List:\"List.cellRenderer\"[Disabled].background",
    laf.getDerivedColor("nimbusSelectionBackground", 0.0f, 0.0f, 0.0f, 0, false));