Check it out:
YUI 3.0.0 beta 1 is now available for download from YUILibrary.com.
This release takes YUI 3 out of its preview phase and brings its APIs to a near-final state. For those intending to implement YUI 3, the 3.0.0 beta 1 release is a good place to begin the transition. If you’ve been working with the latest preview release, George Puckett has provided a comprehensive 3.0.0 beta 1 changelog to guide you. We look forward to hearing your feedback as you begin working with 3.0.0 beta 1, and we’ll work hard to address that feedback as we prepare for a GA release in the coming months.