For example, desktop notifications for Gmail and drag-and-drop file upload in Google Docs require advanced browsers that support HTML5. Older browsers just don’t have the chops to provide you with the same high-quality experience.
As of August 1st, #Google will discontinue support for the following browsers and their predecessors: #Firefox 3.5, #Internet #Explorer 7, and #Safari 3
googledocs.blogsp... — Our plans to support modern browsers across Google Apps - Docs Blog Add comments