Moved from the old JSMin to using YUIMin for compressing the jQuery source. Additionally landed some improvements from #3770 which dramatically reduce the filesize. The final minifed + gzipped size of jQuery went from 19817 bytes to 18063 bytes.

src/core.js

@@ -9,6 +9,9 @@
  * $Rev$
  */
 
+// Will speed up references to window, and allows munging its name.
+var window = this;
+
 // Map over jQuery in case of overwrite
 var _jQuery = window.jQuery,
 // Map over the $ in case of overwrite