Bleeding edge means very new technology. More than Leading edge, Cutting edge or State of the art. A technology which is so new that using it still hurts you (mentally). Produkts which needs more work on it to be practical and useful.
Like cutting edge, only it went slightly too far. Used to refer to technology that is so far ahead of it's time that it doesn't yet have any practical application.
For example, Microsoft Longhorn is bleeding edge because the suggested specs are so ludicrously high that nobody would be able to run it.