So now that we have at least four different implementations of the same thing, the main question is "do we really need them at all?". I know, i know, your first reaction would "OMG, what are you talking about, this is way too cool and i can't wait to use this in my next w00t app". Just look at the number of comments on the three blogs mentioned above (about 40 on Simon's blog, about 40 on mine and even more on Alex's). However, this is only one part of the story.