A couple months ago, new Yahoo! home page went into testing that coincides with the new user interface, YUI 3. The natural approach for building new JavaScript frameworks at Yahoo! is to start with YUI as a base, and that has typically meant the 2.x version. Nicholas Zakas posted on the UI efforts by explaining the goals for the framework of YUI 3:

• Eliminate global dependencies
• Make it small, make it fast
• Create version independence
• Allow code portability
• Be forward compatible

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