This week is a big one for open source browsers, which, as we've pointed out many times, are responsible for most of the innovation going on in the browser arena. The first beta version of Firefox 3.6 is available for Windows, Mac OS X, and Linux, and you can get it here. Meanwhile, Google has delivered a very fast new beta version of the Chrome browser, and it features bookmark syncing so that you can keep your bookmarks streamlined across multiple computers.

Skype for Linux going (almost) open source. The UI will be open, but not the core.

Open source identity: Ruby on Rails creator David Heinemeier Hansson. In this Q&A, he discusses the history of Rails and where it's headed.

5 open source billing systems to watch. AgileBill and others take care of payment processing, invoicing, and more.

Web Open Font Format gets backing from Mozilla. It's an effort to bring advanced typography to the web in a much better way.

Setting up a MySQL cluster for your Linux desktop. It's not so complicated.

Mozilla is out with version 2.0 of its SeaMonkey hybrid browser and email platform, based on Firefox and Thunderbird. There is a long list of additions to the new version, which you can peruse here. SeaMonkey didn't use the exact same core as the Firefox browser before, but now shares the the core of Firefox 3.5.4. Among other things, that means extensions should work more dependably than they did before. Here are some of the other important improvements.