C# Puzzle: What does this program do?

Consider the following code:

class Woot
{
    private static float PI;
    private static bool initialized = doInitialize();

    private static bool doInitialize()
    {
        if (!initialized)
        {
            var thread = new Thread(() => { PI = 3.14f; });
            thread.Start();
            thread.Join();
        }
        return true;
    }

    public static void Main(string[] args)
    {
        Console.WriteLine(PI);
    }
}

What is the output of this program? Is it:

1. 3.14
2. 0
3. Throws exception
4. None of the above

To find out the answer to this puzzle, as well as many others, watch the C# Puzzlers talk with Eric Lippert and Neal Gafter from NDC 2010. How many did you get right?