The latest and greatest version of jQuery , v1.4 is now out. This version comes bundled with many new great features such as per-property easing , new live events ( including submit !) , ability to delay() animations & new focusIn and focusOut events .
Net tuts published an article summarising the new features in jQuery 1.4 .

Download jQuery 1.4 directly from here : http://code.jquery.com/jquery-1.4.js