Just 15 months after its initial release, Google Chrome is now the number three web browser in the world, behind Microsoft Internet Explorer and Mozilla Firefox but ahead of Apple Safari. Of course, beating Safari wasn't hard: That browser has just 4.46 percent usage share because it is used almost exclusively by Mac users. Chrome, like IE and Firefox, is used by the much larger PC user base.

According to Net Applications, IE continues to dominate the web browser market, with nearly two-thirds of all browsing activity, or 63 percent, performed on some version of that browser. Firefox, in second place, commands about 25 percent of the market, while Google Chrome edged up to 4.63 percent. (Also-ran Opera barely makes the top five with 2.4 percent share.)

The news isn't all good for IE, of course. Microsoft's browser has lost an average of 1 percent of usage share for each month of the past year and Net Applications now expects IE to dip below 50 percent usage share by the middle of this year. Most of IE's losses have been gains for Firefox: The Mozilla browser has surged in the past year, though usage was flat in December.

Part of the IE dilemma for Microsoft is that many users are still stuck on the aging and insecure IE 6, which came with Windows XP, another age-old system that is still being used despite superior, modern alternatives. Microsoft has worked to get its customers, especially business customers, off of IE 6 and onto a more modern IE version. That effort has been somewhat successful, but many users have simply moved over to Firefox instead of installing a new IE version.

Looking at December 2009 browser usage more closely, there are some somewhat positive signs for Microsoft: For the first time, IE 8 was the most frequently used browser overall; that browser first shipped in early 2009. IE 6 was number two and Firefox was number three.

For Google, however, surpassing Safari is a big deal and it poises the browser to someday vie for the top spot with IE and Firefox. Those days, of course, are far off. For now, the company can simply look at Safari in its rear view mirror and savor the fact that not everything Apple touches in golden.