When I switched from a Windows PC to a Mac in 2006, I was very disappointed in my choice of Web browsers. As a confirmed Firefox user, I expected Mozilla's Mac browser to be a no-brainer. But after trying Firefox 1.5 and 2.0 for the Mac, I adopted Apple's Safari -- and haven't looked back. Now that Firefox 3.0 is out, though, is it finally the better choice for Mac OS X?

Safari has been the better browser on the Macintosh for a number of reasons. Among the annoyances is Firefox's more Windows-centric way of doing things -- it doesn't closely adhere to Apple's user-interface principles (which admittedly aren't all that well understood or followed by many native Mac applications).

Here's an example: Clicking on the "green + window" button in Safari makes Apple's browser expand to fit the width of the currently-loaded Web page -- a neat trick because in most cases, you don't need the page to be wider than that; you just want to be able to see the whole page. Firefox, however, treats the green button as a Windows-style maximize button, so it always expands the browser to your entire screen. As a cross-platform product, that's not surprising or terribly wrong. But it's an example of a lack of Mac integration that I miss in Firefox.

By far the bigger deal with earlier versions of Firefox concerned performance. Firefox 2 on the Mac OS X 10.4 loaded slowly, especially the first time you launched it after starting up the Mac. It also loaded Web pages sluggishly. In my personal experience, Firefox 2.0 was faster in OS X 10.5 "Leopard," but not by enough to significantly attract my attention.

By comparison, Safari launches very quickly, and its WebKit open-source Web-page rendering engine loads most pages in lickety-split fashion. Initially, I did have a hard time warming up to Safari's squared-off, drab gray look. The best way to describe Safari is Spartan. But in the end, it was Safari's excellent overall performance that decided me.

There are other Mac options, such as Camino, Opera and OmniWeb. All have good points, but each also has glaring problems that rules it out of contention: Camino's lack of extensions and older Gecko engine, Opera's quirky interface and OmniWeb's lack of modern tabs.

Firefox 3 puts in the fix

Mozilla's latest release of Firefox puts a whole new spin on the Mac browser discussion. Firefox 3.0 is noticeably faster than earlier versions. Even Safari stalwarts, such as Computerworld's Mac editor, Ken Mingis, readily agree on that point. The performance difference is apparent -- especially on pages that use complex JavaScript. If Firefox 3.0 had been available when I switched to the Mac, things might have turned out differently.

So what's faster about Firefox 3.0? To find out, I ran Firefox 2.0, Firefox 2.0.1.4, Firefox 3.0 and Safari 3.1.1 through a battery of objective tests. I used the SunSpider JavaScript Benchmark, which showed me that Firefox 3 bests today's Safari by a small amount of time.

The big news, though, is that Firefox 3 processes JavaScript more than three times faster than Firefox 2. I also ran tests loading 10 multiple tabs simultaneously and other page-load tests. Firefox 3 edged out its predecessors and Safari 3.1.1 by a small margin in those tests. On paper, it's the currently fastest.

There is one downside to Firefox 3, however. The first time you launch it after starting up OS X, Firefox 3 takes 5.5 seconds to open a blank page. By contrast, Safari 3.1.1 takes about half a second for the same task. It's a noticeable difference. If you're the kind of person whose Mac is always running, though, it's a moot point.