Mozilla recently released the first beta version of Firefox 4, the next iteration of the world's second most popular browser (after Internet Explorer). The new Firefox offers the usual under-the-hood tweaks you'd expect, such as improved security and better page rendering, and it also supports WebM, Google's new open video standard project. But more importantly to the average user, Firefox 4 offers a refreshed layout and appearance. Here's a look at some of the highlights.

New Menu

If you're a Windows Vista or Windows 7 user, one of the first things you're likely to notice is that the menus have been moved to a single orange Firefox button on the upper left side. (Mac OS X, Linux, and Windows XP users will continue to see the regular menu layout across the top of the screen.)

Mozilla has also merged the stop and reload functions into one button on the far left side of the screen. All operating systems will see this new feature.

Tabs on Top

Taking a cue from Google Chrome, Firefox 4 beta now has the browser tabs pointing upwards by default instead of hanging down from the top of the window. This is a great addition to Firefox as it helps to maximise screen real estate for the web page you're viewing. Right now, Mozilla says this feature is only available for the Windows beta right now, but will be rolled out to Mac and Linux users in the future.

If tabs on top are not your thing, you can switch back to the more traditional Firefox tab layout by right-clicking the tool bar and deselecting the "Tabs on top" option. In Windows Vista and Windows 7, you can also go to the Firefox Button on the upper left side and select Customise>Tabs On Top.

Bookmarks

The bookmarks menu has been moved to a new bookmarks button on the upper far right side.

While the bookmarks layout has changed, the functionality is the same; to access your bookmarks just click on the star and select from the drop down menu.

Switch Tabs in Awesome Bar

If you like to keep numerous tabs open at a time, Firefox now lets you search for the tab you want right from the Awesome Bar. This is a great alternative to cycling through all your tabs with keyboard shortcuts or your mouse.

To access the switch tabs function, just place your cursor in the Awesome Bar (that's the URL entry field for you Firefox newbies), and start typing name of the site or page you want to access. The Awesome Bar will start showing you a few options for past and current sites. One of the top options should be the tab you're looking for, and will be marked as "Switch to tab" (see photo). Just select that option, hit enter, and Firefox will switch to the tab for you.

Privacy, Crash Protection and HTML 5

In addition to the obvious new user features, Firefox 4 beta 1 has also added a few features under the hood. Mozilla has added crash protection for your Flash, Quicktime, and Silverlight plugins. This means if the Flash Player crashes in one tab, it won't take the entire browser with it.

Firefox 4 beta is also getting more HTML 5 capability including the ability to display CSS Transitions, like a Web page background gradually shifting from white to black.

Mozilla has also bumped up its privacy protection, by closing a loophole that could allow a malicious script to sort through your browser history, exposing you to identity theft.

Overall, Firefox 4's new look and added features look promising, and it will be interesting to see what other features Mozilla adds to future beta releases of Firefox 4.

If you're thinking about trying out Firefox 4 beta 1, you can find it here. But keep in mind that Firefox 4 is a work in progress. So you may have to deal with a few unexpected bugs and crashes. If you'd rather not deal with the headache, you might want to wait for the official launch of Firefox 4 scheduled for later this year.