Opera has long been the underdog in the desktop browser wars, but it’s easy to forget that a lot of the browser design and features we take for granted today were actually pioneered by the Norwegian company. Opera 11.50, which launched for Windows, OS X, FreeBSD and Linux today, offers a few interesting new features, as well as a more streamlined design that make it worth another look. Among the new features are password synchronization with other Opera browsers and extensions for the browser’s Speed Dial feature. Opera’s new core rendering engine is now also noticeably faster and developers will find some new tools for HTML5 development in this new version.

While Opera highlights the new sleeker look of the browser, the differences between this new version and the last are actually relatively subtle. There can be no doubt, though, that Opera 11.50 looks more streamlined and actually feels significantly faster than the last version.

The most interesting new feature, though, is definitely the new extension architecture for Opera’s Speed Dial. If you’re not familiar with Speed Dial, just imagine Chrome’s new tab button on steroids. Speed Dial is now configured to automatically resize its previews to accommodate as many shortcuts as you want and developers can actually write little widgets that can live in these previews. Among today’s launch partners are Read It Later, Webdoc, music service The Hype Machine and StockTwits.