Google Chrome is available in three versions, a stable, mainstream version, and a beta version, as well as a cutting-edge developer version. Today's updates were already available in the beta version, but for most users who are unlikely to even know that the other development tracks exist, these updates will represent a major step forward.
Improved New Tab Page, Autofill, Full Screen Mode
Chrome can now also autofill forms with information a user has previously entered into similar forms, and Chrome finally got a full-screen mode that hides the title bar and the rest of the browser window.
Sadly, though, one neat feature that was available in the beta versions, the ability to drag tabs to see them side-by-side, did not make it into the stable version, yet.
The developer version already contains some rudimentary support for adding extensions and user-scripts, but it will probably still take a while before these features will make it to the stable version of Chrome.
If you are already using the stable version of Chrome, these updates will be applied automatically, and if you are not using Chrome yet, you can download it from here. Officially, Chrome is only available for Windows, but if you are a very brave Mac user, you can download an unstable and highly unpolished version of Chrome here.