Google doesn't support older versions of Chrome either and Chrome is silently updated to the latest release, it's not dumb, it's smart. If you want a repeat of IE6 debacle, thats your choice, most web developers would hate if old browsers impede their ability to deploy the latest web technologies.
For web applications to spring even farther ahead of traditional software, our teams need to make use of new capabilities available in modern browsers. 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.
For this reason, soon Google Apps will only support modern browsers. Beginning August 1st, we’ll support the current and prior major release of Chrome, Firefox, Internet Explorer and Safari on a rolling basis. Each time a new version is released, we’ll begin supporting the update and stop supporting the third-oldest version.
As of August 1st, we will discontinue support for the following browsers and their predecessors: Firefox 3.5, Internet Explorer 7, and Safari 3. In these older browsers you may have trouble using certain features in Gmail, Google Calendar, Google Talk, Google Docs and Google Sites, and eventually these apps may stop working entirely.
As the world moves more to the web, these new browsers are more than just a modern convenience, they are a necessity for what the future holds.