Apple announced the release of the public beta of Safari 4 today claiming that its “Nitro” engine runs JavaScript 4.2 times faster than its previous incarnation.  More new features include: Top Sites, a way to stimulate internet overload by viewing your most frequently visited pages all at once; Full History Search, in which the user can search through titles, web addresses and the complete text of recently viewed pages; Cover Flow, to flip through web history or bookmarks just like you’re used to in iTunes; and Tabs on Top, which makes managing tabs easier and your browser window that much larger.

“Apple created Safari to bring innovation, speed and open standards back into web browsers, and today it takes another big step forward,” said Philip Schiller, Apple’s senior vice president of Worldwide Product Marketing.

Indeed, Apple claims that the new Nitro JavaScript engine executes JavaScript up to 30 times faster than IE 7 and more than three times faster than Firefox 3.  Similarly, Safari 4 is said to load HTML web pages three times faster than IE 7 and almost three times faster than Firefox 3.

Safari 4 also includes HTML 5 support for offline technologies so web-based applications can store information locally without an Internet connection, and is the first browser to support advanced CSS Effects that enable highly polished web graphics using reflections, gradients and precision masks.

Safari for Mac, Windows, iPhone and iPod touch are all built on Apple’s WebKit, which the company calls “the world’s fastest and most advanced browser engine”.  Apple developed WebKit as an open source project to create the world’s best browser engine and to advance the adoption of modern web standards.  Most recently, WebKit led the introduction of HTML 5 and CSS 3 web standards and is known for its fast, modern code-base.  The industry’s newest browsers are based on WebKit including Google Chrome, the Google Android browser, the Nokia Series 60 browser and Palm webOS.

New features in Safari 4:

- Top Sites, a display of frequently visited pages in a stunning wall of previews so users can jump to their favorite sites with a single click

- Full History Search, where users search through titles, web addresses and the complete text of recently viewed pages to easily return to sites they’ve seen before

- Cover Flow, to make searching web history or bookmarks as fun and easy as paging through album art in iTunes

- Tabs on Top, for better tabbed browsing with easy drag-and-drop tab management tools and an intuitive button for opening new ones

- Smart Address Field, that automatically completes web addresses by displaying an easy-to-read list of suggestions from Top Sites, bookmarks and browsing history

-Smart Search Field, where users fine-tune searches with recommendations from Google Suggest or a list of recent searches

- Full Page Zoom, for a closer look at any website without degrading the quality of the site’s layout and text

- Built-in web developer tools to debug, tweak and optimize a website for peak performance and compatibility

- New Windows-native look in Safari for Windows, that uses standard Windows font rendering and native title bar, borders and toolbars so Safari fits the look and feel of other Windows XP and Windows Vista applications