While Mozilla lights a fire under competing browsers with support of emerging Web standards with Firefox 3.5, it can still improve its performance, reliability, and usability.

Firefox has the misleading status of second most popular browser. Two-thirds of all sites are still visited by some version of Internet Explorer. It’s no secret that Microsoft only wins because the majority of computer users run Windows and aren’t quite savvy enough to make a conscious decision about which browser to use. In fact, when 50 people in Times Square were asked, “What is a browser?”, most confused it with a search engine.

However, with somewhere between 20 and 30 percent of the browser market, Firefox has the distinction of being the most popular browser chosen by individuals who actually consciously think about what browser to use.

In recent months, the competition has stepped up its game. Apple’s Safari has achieved notable speed gains, Google Chrome came out of nowhere to redefine the browser as clean, fast, and simple again, and IE8 has some impressive new features.

With version 3.5, Firefox has also stepped up. In some ways, it is redefining the Web with support for HTML5 which supports video without a plug-in, and with other new technologies like native JSON, Web worker threads, downloadable fonts, and CSS media queries. These technologies will improve Web-development and, therefore, the user experience.

Firefox 3.5 has caught up in some key areas. It improved its speed with its new Gecko 1.9.1 rendering engine and TraceMonkey JavaScript engine. It borrowed from Google Chrome the break-away tab feature, which lets you drag a tab from the main browser window into its own window. This feature is highly useful in multi-monitor setups where it’s desirable to compare two pages side-by-side. Finally, Firefox 3.5 adds Private Browsing Mode (aka "porn mode"), which all other mainstream browsers already had.

Impressive as it is, if Firefox 3.5 wants to stand head and shoulders above the competition, it needs implement some of the features that still distinguish Safari, Chrome and Internet Explorer.

Chrome, which is my current favorite browser, leads in a couple ways. It improves reliability by running one process per tab so that a single tab crash doesn’t take down the entire browser. Chrome also excels with its clean interface. This is especially important for netbook users. Firefox should take a page from Google’s book on creating an efficient UI by integrating the search bar into the location bar and by using less space with the title bar.

Firefox still trails with its lack of new tab features. Chrome and Safari both show you your most commonly visited sites when a new tab is opened. Of course, Firefox has an extension available for almost anything, but it would be nice to see this functionality out of the box.

Internet Explorer 8 includes one feature I think Firefox and others should replicate: Colored Tabs. Links spawned into different tabs from the same page are color-coded. It’s a great feature to differentiate articles opened from CNN from those opened from Reddit, for instance.

Of course there is one area in which Mozilla Firefox has IE, Chrome and Safari beat, and that’s the ability to run on Windows, Linux, and OS X.

Michael Scalisi is an IT manager based in Alameda, California.