The focus is centred on the top of the stem and so a lot of the seed fluffy bits are out of focus because the depth of field is so narrow on macros. This and the very white nature of the seeds appear slightly over exposed. I think that dropping the exposure down a little would help the definition of the seeds and perhaps trying a more forward focus point. The blurred background works well and frames the seed head nicely, although a perhaps off centre subject would be better. See for example <a=href"http://www.caedes.net/Zephir.cgi?lib=Caedes::Infopage&image=Pixleslie-1277168598.jpg">this image for what I mean about off centre.
This is lovely. (: I'm detecting a little bit of grain in the background - and the image is, perhaps, slightly off focus, as well - but the colors and lighting are very nice. Definitely a job well done.
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I like it. These things are most difficult to make perfect, especially close up. Many times, on the water, I too had my share of waiting for the wind. Nice shot.