A few highlights:
- WebKit rendering engine. Used in different products such as Apples' Safari. Originally part of the KDE project. Becoming increasingly popular.
- Tab-sandbox. Each tab runs in a sandbox, which means that if one tab crashes, the others remain operational. Also, if you log in on one tab, you're not logged in on other tabs. Sessions are tab-scoped.
- Tabs are more than just a web site instance. They're a browser instance. Each tab has its own forward & back buttons, its own addressbar and so forth. We saw this design in early beta's of Internet Explorer 7.