Google caused quite a ruckus last year when they announced that they were dropping support for Internet Explorer 6. Even Microsoft has supported the move away from IE6, due to the various issues that brings with it - security being a primary concern.
At over 10 years old, many people would agree that IE6 was long in the tooth and well overdue to being scrapped. However this does bring up the question - if 10 years is too long to support a browser, even a browser that at one point claimed nearly 90% of the browser market, then how long should a browser be supported?
Google appears to have come up with the answer as they have just announced future plans to drop support for Firefox 3.5, Internet Explorer 7 and Safari 3 from August 1st. From then on, Google only plans to support the current and previous major release of each browser.
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.
Mozilla has plans to release Firefox 5 in a few weeks time, meaning that by the time that August 1st deadline hits, support for Firefox 3.6 could be dropped as well.