I don't think the blur necessarily added to this shot. Blur is hard - for examples of how to do it well, see nshapiro's portfolio. His secret is color - very rich color - and smoothness. Everything is smooth and blends well. I've tried to emulate it and failed. This is a bit more jagged than smooth, if that makes sense, and really needs some contrasting color as well.
This was a hard challenge and almost everyone scored low. It it is nature for us to want to see things in focus and sharp and while blur and soft focus and work, more often it doesn't. This has a nice abstrat feel but I don't think the blur added anything to the shot, which is what people were looking for in this challenge. The color is nice and the compositon seems nice but as I stated the blur doesn't make your subject anymore interesting, just blurry. I would have voted this a 5.