John Resig wrote a good piece on the new querySelectorAll.all() api on hacks.mozzila.org. document.querySelectorAll() give you a better grip on CSS selection. For exemple, if you want to get every span in p tags, you would write document.querySelectorAll(“p span”), which is a huge improvement over the older DOM technics. This API can be used with all major browsers excluding IE6, IE7 and only CSS 2.1 selector for IE8.

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