When using code completion to complete "Runnable r = new Runnabl", I get the following result with my formatting 
options:

    Runnable r = new Runnable() {

        public void run()
        {
            throw new UnsupportedOperationException("Not supported yet.");
        }
    }

There are two things that are wrong with the result:

1) The opening brace after "new Runnable()" should be on the next line, as I have "Braces Placement" set to "New Line" 
for "Class Declaration" in the Formatting options. (!nd also for "Other" in case that matters--which I don't think it 
should.)

2) There should be no blank line before the run() method implementation, as I have "Blank Lines" set to 0 for "After 
Class Header" in the Formatting options. The "Before Method" setting should not be applied at the beginning of a class 
body (see issue 110176).

In general, the generated code should have the same formatting as Source -> Format would produce. With the example 
above, this would be:

    Runnable = new Runnable()
    {
        public void run()
        {
            throw new UnsupportedOperationException("Not supported yet.");
        }
    }

Product Version: NetBeans IDE 6.0 (Build 200711261600)
Java: 1.6.0_04; Java HotSpot(TM) Client VM 10.0-b19
System: Windows XP version 5.1 running on x86; Cp1252; en_US (nb)