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Actually i am sorry i am not clear your this point.i have tried a lot but can't.will you please explain ? " Setup your theme and templates to use structured data in the HTML. This will tell Google specifically what your pages and products are best categorized as. http://schema.org. You can use this especially for product reviews which may show up as rich snippets in the search results "

Nit-picky I reckon.  Yslow is great for diagnosing a problem. I'm not sure it is best used as a strict checklist. If the script is loading asynchronously then it should interfere with the user experience which is what counts.