For Chrome users, and thanks to HTML5 Desktop Notifications don’t have to miss new emails and chats in Gmail just because you aren’t in your Gmail window. Maybe you’ve switched to a different tab, browser or program and missed an important reply via Gmail or Gmail chat? No more, thanks to HTML5 Desktop Notifications.
Google has thought this new feature out, so you can enable notifications for Gmail, or Chats, or both; and you’ll get a popup notification whenever you get a new message.
Google is already planning to make desktop notifications available for other browsers so that you can enjoy it even if you don’t use Chrome.