Jun 1, 2011 12:09 GMT  ·  By

More than one in a dozen Windows 7 users have upgraded to Internet Explorer 9, and are actively using the browser on a daily basis, according to statistics made available by Internet metrics company, Net Applications. With over 350 million Windows 7 licenses worldwide, I think it’s quite easy to at least get an idea of just how many customers already made the jump to IE9.

Microsoft’s Roger Capriotti, Director, Internet Explorer Product Marketing, revealed that worldwide IE9 usage share on Windows 7 increased by no less than a 60% between April and May 2011.

In this regard, IE9 usage by customers also using Windows 7 shoot up to no less than 12.2% in May globally, and it’s even larger on some markets.

“We continue to see good momentum around Internet Explorer 9 on Windows 7 this month. In the US, IE9 has now passed 17% usage share on Windows 7 as of the last few days in May,” Capriotti added.

“As we mentioned last month, we built IE9 to help developers unleash faster and richer web experiences by tapping into the capabilities of Windows 7 and modern PC hardware. For Windows 7 customers, the best browser for experiencing these web experiences is IE9.

“And the good news is with the recent release of 53 additional languages last month, IE9 is now available to more and more Windows customers with a total of 93 languages supported – more than any other browser on Windows.”

The software giant is not revealing the number of IE9 downloads since RTW earlier this year. This is because the number won’t be favorable to the company, especially when compared to Firefox 4.0.

In Contrast, Mozilla is touting almost 200 million Firefox 4.0 downloads since the latest major version of the open source browser was launched.

However, despite the huge number of downloads, on Windows 7 at least, Firefox 4.0’s usage share is just a little bigger than IE9, namely 14.05%, vs. IE9’s 12.2%.

When taking into consideration all operating systems however, Firefox 4.0 has a clear advantage over IE9, with an usage share of 10.08%, compared to only 4.19%.

IE9 only supports Windows 7 and Windows Vista, while Firefox 4.0 also plays nice with Windows XP. If the following growth trend continues, Firefox 4.0 will become the second most used browser in the world next month, behind Internet Explorer 8 which is still the king with a usage share of 31.28%.

Overall, Internet Explorer continues to lose usage share to its rivals, and is now down to 54.27%. Firefox climbed a tad since April 2011, now up to 21.71%. Google Chrome accounted for the most consistent increase, a boost from 11.94% in April to 12.52% in May 2011.

Safari is at 7.28% and Opera at 2.03%, the first increasing in terms of usage share, the later decreasing slightly, and coming dangerously close of going under the 2% mark.

It will certainly be interesting to follow the evolution of browser usage over the coming year, especially since more and more users will migrate to Windows 7. Microsoft estimates that no less than 350 million new Windows 7 PCs will be sold this year alone.

Internet Explorer 10 (IE10) Platform Preview 1 (PP1) is available for download here.

Windows Internet Explorer 9 RTW for Windows 7 and Windows 7 SP1 is available for download here.

Firefox 4.1 for Windows is available for download here. Google Chrome for Windows is available for download here.

Opera 11.10 Final is available for download here.