Gmail Desktop Notifications in Chrome [Google Introduces Browser-Based Google Mail & Gmail Chat Notifications via HTML5, but Currently Works Only in Chrome]
If you’re like me, you probably expect important and find yourself constantly checking your Gmail window or tab for new messages. Now you don’t have to install third-party Gmail inbox checkers or even Gmail’s own notifier to get email alerts, as Gmail supports notifications via browser.

HTML5′s main purpose is to incorporate dynamic content into websites without the need for third-party add-ons. While the HTML5 spec is still under works, Google has incorporated a pop-up mechanism for Gmail notifications in Chrome.
The system is only available in Google Chrome for now, but Google is working on enabling the system for use with other browsers. You can access the notification feature by clicking the Settings link in Gmail and looking for the Desktop Notifications portion. You can choose to enable Google chat notifications. You also have the option to turn on Gmail notifications for all inbox items or just priority inbox items.
Notifications will appear on your desktop (near the system tray), and this will be independent of any browser window positioning. This should work as long as you have a Gmail window open. No word when this will be enabled for Gmail for domains, though.
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