Opera 35 features tab audio muting, improvements to download management, a separate search box, and access to more settings. The Webkit-based version of Opera is finally starting to look like the browser it replaced, although we’re not quite there yet. Tab control is still somewhat lacking: there’s no setting to switch to a new tab automatically, for instance.
The new version includes numerous other changes and bug fixes, including several related to stability. The unified change log for Opera 35 provides a brief overview of the changes, while the full change log gets into the technical details.