Long awaited extensions and bookmark sync features of google chrome came out of beta yesterday. All the chrome users will get the update through their current browser. If you are looking to update your google chrome to support extensions, go to About Google Chrome under settings, and click update to new version.
The bookmark sync is a simplified version of Google's browser sync (earlier released for firefox). it works on your gmail account, and you can set time interval of the bookmark updates.Google also has published a video explaining the new bookmark sync feature here.
But the major upgrade is the support for extensions lack of which was one of main reason for many still sticking with Firefox.With the introduction of extensions the growth in share of Google Chrome is expected to skyrocket. As Google was working with developers on extensions even before the official stable release support , most of the popular extensions of Firefox are now available for Google chrome here.
You can read the Google's official release on Google Blog.