Mozilla has begun building a new technology called IonMonkey into Firefox to improve its JavaScript performance.
High JavaScript performance is essential in today's hotly competitive browser market, because JavaScript is the language behind complicated Web sites and Web apps such as Google Docs and Facebook. IonMonkey has now been packaged into the "nightly" version of Firefox 18 for hardcore developers; that version is scheduled to become the mainstream version of the browser early in 2013.
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Mozilla juices Firefox's JavaScript with IonMonkey | Internet & Media - CNET News