Apple today during the WWDC 2009 keynote announced that Safari 4 is now available as a pubic release after a short period in beta testing.

Safari 4 features the Nitro engine which runs JavaScript up to 4.5 times faster than Safari 3. Safari 4 makes browsing more intuitive and enjoyable with innovative features, such as Top Sites, Full History Search and Cover Flow, and support for modern web standards like HTML 5 and advanced CSS Effects.

“The successful beta release helped us fine tune Safari 4 into an even better, faster version that customers are going to love,” said Philip Schiller, Apple’s senior vice president of Worldwide Product Marketing. “Safari is enjoyed by 70 million users worldwide and with its blazing fast speed, innovative features and support for modern web standards, it’s the best browser on any platform.”

Safari 4 is built on the world’s most advanced browser technologies including the new Nitro JavaScript engine that executes JavaScript nearly eight times faster than IE 8 and more than four times faster than Firefox 3. Safari quickly loads HTML web pages more than three times faster than IE 8 and three times faster than Firefox 3.

Safari 4 is available for both Mac OS X and Windows as a free download at www.apple.com/safari.