Google has begun pre-beta trials for Chrome 2.0. The focus of Chrome 2.0 is on the implementation of a number of new features, including some key features missing from the first version. In addition, some bug fixes and security updates have been made as well.

Updates to the Chrome browser include the addition of form auto complete (one of the features most obviously missing from the initial release that lets Chrome remember what has been typed into fields on Web pages), full-page zoom, spell checking improvements, and auto-scrolling.

Google on Thursday released the pre-beta, officially called 2.0.156.1, to its Dev Channel, which is where developers get a chance to take a look at possibly new features.

Moreover Google said Friday it hopes to release versions for Mac OS X and Linux by the first half of the year and released a new version Wednesday that paves the way for the most requested feature, extensions. Brian Rakowski, Chrome's product manager, said the company wants to release Chrome for Mac and Linux before the first half of 2009 is up.

Both Mozilla, the maker of Firefox, and Microsoft, whose Internet Explorer still accounts for nearly 70% of all browsers, rely on periodic major updates that go through long periods of beta testing. Mozilla, for instance, is working through beta testing of Firefox 3.1, the successor to Firefox 3.0, which launched in June 2008.

Until now, Google has only offered Chrome on Windows in two versions, the Stable-channel and the Dev-Channel. With the latest dev-channel release, Google is adding a third development milestone release with a Beta-channel as well.