Opera has announced the full release of version 10.50 of its desktop browser for Windows - a rather speedy transition from the beta, which was only released a few weeks back. It's a rather substantial upgrade from Opera 10.1, featuring a dramatic UI refresh and an overhaul of Opera's Presto rendering engine.

The UI now shares a lot of similarities with Chrome. Tabs are in the title bar, there are smaller buttons, a condensed address and status bar, and an "Opera Menu" which does the same things that the old menu bar used to. It also now has private browsing functionality, which has been dubbed "porn mode" in other browsers.

Opera says: "We have gone from Pre-Alpha to Final in just over two months (with a Christmas holiday in between I might add). Never has the development of the desktop browser been so fast. Our developers are rivalling (rendering engine) Carakan for speed!"

The rendering engine improvements - in both javascript and graphics - lead Opera to claim that 10.50 is the "fastest browser available on the market". It also has the Turbo, Unite and Link functionality that aren't available in other browsers. Mac and Linux versions should follow soon.