Eric Lippert's challenge “comma-quibbling”, best answer?

Question

I wanted to bring this challenge to the attention of the stackoverflow community. The original problem and answers are here. BTW, if you did not follow it before, you should

Answer 1

Just for fun, using the new Zip extension method from C# 4.0:

private static string CommaQuibbling(IEnumerable list)
{
    IEnumerable separators = GetSeparators(list.Count());
    var finalList = list.Zip(separators, (w, s) => w + s);
    return string.Concat("{", string.Join(string.Empty, finalList), "}");
}

private static IEnumerable GetSeparators(int itemCount)
{
    while (itemCount-- > 2)
        yield return ", ";

    if (itemCount == 1)
        yield return " and ";

    yield return string.Empty;
}