Apple on Friday reported that Safari 4 has been downloaded more than 11 million times in the first three days of its release, with more than half the downloads for Windows.

Apple released the latest version of is Web browser Monday at the company's Worldwide Developers Conference in San Francisco. The company claims Safari 4 runs JavaScript and loads Web pages much faster than rivals Internet Explorer and Firefox.

Of the more than 11 million downloads as of Wednesday, more than 6 million were for Windows, according to Apple. Philip Schiller, senior VP of worldwide product marketing, crowned the browser "an incredible success" in a statement on Apple's Web site.

Marketing aside, Safari in May was a distant third in the global browser market share behind Microsoft's Internet Explorer and Mozilla's Firefox, respectively. IE had a 65.5% share, Firefox 22.51%, and Safari 8.43%, according to Web metrics firm Net Applications.

Safari use has risen slightly since January, when it had an 8.29% share, but Firefox saw a bigger gain of nearly 1%. IE, on the other hand, fell more than 2%.

Among the most important new features in Safari is what Apple calls a "Nitro" engine that runs JavaScript up to 4.5 times faster than Safari 3. Apple claims independent testing shows the new browser executes JavaScript nearly eight times faster than IE 8 and more than four times faster than Firefox 3.

Apple is making similar claims when in comes to loading HTML Web pages. In that task, Safari 4 is more than three times faster that its two rivals, according to the company.

Mac users are expected to see an even bigger boost in September with the release of Mac OS X Snow Leopard, available in September, Apple said. That's because the 64-bit capabilities of the upcoming operating system speeds up the rendering of images and the running of scripts.

Safari currently has 70 million users worldwide, according to Apple.

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