One of the things that changed was COM. (COM used to mean "Component Object Model", but the technology has expanded so much that a description that limiting is just inaccurate ... so it just means "COM" today.) .NET has replaced COM and it's reliance on the Registry as a central catalog of what is on your computer and how to use it.
Except ... for Office.
Office , even the latest version, Office 2003, still depends on COM. And it still uses good ol' Visual Basic 6 as the software base. (Well ... technically, VBA 6.3, but the differences aren't that earth shaking.) Microsoft was willing to "pull the rug" out from under all of the professional developers with .NET ... but not their desktop users. The problem is that Office just makes too much money and not even Microsoft could take that much risk all at once.
