You shouldn't read too much into Google Chrome's version numbers. Just because you can now install Google Chrome 3.0, it doesn't mean that Google wants to appear more mature than it already is. For Chrome, version numbers are just a way to highlight major milestones.
Three months after the first developer preview, Google Chrome 3.0 is out of beta and ready to replace the current stable version. Since Google updates the browser automatically, you might not even notice that you use a version that brings new features.
Even if it's one of the fastest browsers available today, Google Chrome continues to improve its performance. "We've improved by more than 150% in Javascript performance since our very first beta, and by more than 25% since the most recent stable release," mentions Google.
The new release supports themes so you can customize the browser with one of the 28 new themes. Not all of them are good-looking, but they're easy to install and you don't have to restart your browser after changing the theme.

Google Chrome 3.0 has an updated new tab page that lets you customize the pages reordering them using drag and drop, by pinning the pages you use frequently and removing the pages you no longer visit. Google simplified the page by removing the list of search boxes and the recent bookmarks.
(Tip: you can still use the previous new tab page design, by appending this flag to a Chrome shortcut: --old-new-tab-page.)
http://googlesystem.blogspot.com/2009/09/google-chrome-30.htmlas a webmaster what's your comment about d chrome browser.