For sure, there are power users who covet Office's handling of macros and complex forms. And there are plenty of corporate employees who swear by Office as a SharePoint and other line-of-business applications.

They'll likely be among the first to sign up for Office 2010's beta, which will Microsoft said today. The final release of Office 2010 is scheduled for the first half of next year.

For most users, the last 'must-have' feature debuted by Office was But companies stay on the Office upgrade treadmill -- despite the $155 annual per-head tax to do so -- mostly out of the "tremendous inertia" the software has built up over the last 20 years, according to Paul DeGroot, an analyst with the independent firm, Directions on Microsoft.

Every new version of "the Office suite gets more and more components," he said, "and even though most people won't use most of them, you only need someone to depend on one of them to make it sticky."

Chris Capossela, senior vice president of the Information Worker group at Microsoft that produces Office, doesn't take exception to that characterization. "The fact that employees don't use every nook and cranny of Office doesn't reflect much," he said in an interview last month. "I challenge you to tell me how many of the features of your Tivo do you really exercise? Could it do a lot more stuff than you use it for?"