The Lifecycle of Microsoft Office
We recently noted that Microsoft Office 2004 will hit its end-of-life date (after which it won't receive any more updates) on 13-Oct-09. You can look up this date for other Office products at Microsoft's Web site, or just keep in mind that Microsoft offers "mainstream support" for a minimum of 5 years or 2 years after the successor product is released, whichever is longer.