Opera has released version 11.50 of its desktop Web browser. The significant update introduces Opera's new "featherweight" user interface and brings a number of other new features and performance improvements.

The major browser vendors have all been working to simplify their user interfaces and reduce the amount of functionality that is exposed in their default layouts. Opera took a big step in that direction with the 10.50 release last year, when they hid the menu bar by default. The new "featherweight" interface takes the existing streamlined layout and overhauls it with a much more consistent style.

In our review of 10.50 last year, we highlighted the strengths of the streamlined layout but had a lack of enthusiasm about the feel. The issue is that simplifying an interface by pulling out elements tends to detract from the seamlessness and sense of balance. To get it right, Opera really needed a more holistic redesign of the navigation and tab interface—with an approach that takes the new simplified layout into consideration from the start.

That seems to be exactly what the browser maker is doing with the "featherweight" project. The execution is great and the impact it has on the quality of the user interface in 11.50 is very positive. The Mac theme in particular has largely gotten past the "uncanny valley" effect that it exhibited in previous versions.

The Windows theme already had a pretty good native feel in 11, but Opera has still managed to bring it up a notch in 11.50. The menu jewel in the titlebar is less visually intrusive and the toolbar looks less cluttered due to the removal of the button borders. The status bar at the bottom of the window is much easier to see in 11.50 because the designers gave it an opaque background instead of leaving it in the window's glass frame.

The new design cuts some of the extraneous visual noise. For example, Opera used to show colored dots on top of tabs to indicate when the tab's content has changed. The dots are gone in 11.50 and have been replaced with a really subtle artwork change that makes the tab look like its top-right corner is creased backward.

The new featherweight style in Opera 11.50 really brings the browser's interface up to the same level of quality as Chrome. It's seamless, streamlined, and distraction-free. The only part that could still use some work is the sidebar. Opera's sidebar is a useful feature and a noteworthy advantage that the browser has over Chrome, but the visual style of Opera's sidebar makes it feel like it is bolted on as an afterthought. It's especially noticeable in OS X, where the heavy gradient breaks the visual continuity of the tab and navigation bar.

In a blog entry about the featherweight design, Opera developer Jan Henrik Helmers says that the changes we see in 11.50 are just the first phase. It's likely that further improvements to the look and feel will materialize in future versions as the featherweight project matures. It's off to a really good start in 11.50.

"Our goal has been to make Opera as light, bright and user-friendly as possible—without sacrificing power or flexibility. We want the user interface to match the speed of our rendering engine," Helmers wrote. "Some changes are highly visible, such as those to the address and status bars, but you will find that we have reworked much of the skin throughout—including a brand new icon set."

Part of what makes the simplified interface so impressive in Opera 11.50 is that the browser's traditional configurability and advanced power-user features didn't have to be sacrificed in order to get to this level of usability. It still offers full control over the layout of the tabs and navigation elements.

Opera has generally only appealed to extreme power users because it has a lot of functionality that most people wouldn't want in a browser. Its dizzying array of perversely exotic features includes a Web server, and built-in clients for e-mail, BitTorrent, and even IRC—it is just one text editor short of being the emacs of the Internet.

But over the past several versions, Opera's move to a more streamlined interface has pushed aside this clutter so that it doesn't stick out at odd angles. All of those features are still included for users who want them, but they aren't a distraction anymore. That shift was mostly accomplished in the 10.50 release last year, but the new featherweight style has added the necessary level of fit and finish to make it really shine.

The more user-friendly design still probably won't advance Opera into the mainstream browser market, but it will modestly expand the browser's niche to include users who want simplicity and performance without giving up configurability. Despite its growing advantages, Opera still falls short in some key areas. Its add-on ecosystem has a lot of gaps and isn't well-supported by major add-on vendors. Opera's other major weakness relative to Chrome is its lack of process isolation for tabs.

In addition to the user interface changes, 11.50 also got some performance and feature improvements. The Opera Link synchronization system was improved to handle password synchronization between instances of the browser. Graphics rendering speed got a boost, particularly for SVG content.

The speed dial interface was overhauled with a flexible layout system that will allow users to have an infinite number of speed dial items. A new speed dial extension system makes it possible to have speed dial tiles that programmatically display information—a bit like the Live Tiles concept from Windows Phone 7. We tested a StockTwits speed dial extension that shows the prices and recent activity of popular stocks.

The new version of Opera is available to download from the company's website. According to the company's download counter, the number of Opera 11.50 downloads easily exceeded the total population of the Death Star.

Listing image by Photo by Steinar B