ReadWriteWeb

The beta version of the Opera 11 browser just launched this morning with a notable new feature: tab stacking. Traditionally, tabs were opened side-by-side, says the company, now Opera users can stack tabs on top of each other instead.

The result isn't as messy as it may sound - in fact, it could become a must-have for tabaholics who typically keep a dozen or more tabs open at any time. But is it useful enough to get you to switch?

We expect to see the first beta version of Firefox 4 later this month. If you want to try out some of the changes that Mozilla plans to make to its browser today, however, you can also download the latest Mozilla Developer Preview. This new version offers support for WebM video, hardware-accelerated HTML5 video for Windows (DX9), Mac (OpenGL) and HTML5 forms. The Mozilla team also managed to vastly improve the performance of the browser. Windows users will see major interface improvements, and users on all platforms can now choose to put tabs on top, just like in Google Chrome.

You open a fresh new tab on your browser and what do you see? If a blank white screen feels like infinite potential to you, you're not alone. Mozilla feels the same way and is working on figuring out what to put in that space.

Mozilla Labs posted a new proposal today to put frequently visited page thumbnails in the very corner of new tabs and to perform contextual actions automatically, based on what you were doing on your last tab. For example, if you've highlighted a street address on one tab, Firefox might open a map of that address automatically in a new tab.

One of the best features in Google's Chrome browser is the way it handles tabs. In Chrome, when you click a link, the tab that opens appears to the immediate right of the current tab. It may seem like a small thing, but when you have so many tabs open in Firefox that they spill off the sides of the screen, having to scroll to the end to see the new web page is annoying and inefficient.