XDocs, a new application being developed by Microsoft, will apparently be called InfoPath, according to eWeek, though it is still not clear if it will be bundled with Office 11, which is now in beta. The problem with XDocs is that it is a hugely valuable application to the people who can use it, but it's far from clear that that includes the average Office user. So what is it? Basically it's a forms application, of the sort you'd create for an HR or healthcare or manufacturing application. However, it allows you to create forms that look and work more like documents. One of the major failings of forms, as opposed to documents, is that the spaces are either too long or too short for what you want to enter, and there's nowhere to add comments or whatever. With the XDocs implementation of a form, those problems are avoided because the user can manipulate the form like a document. However, it doesn't break the application because all the data still get validated according to the rules. The rules, obviously, are embodied in the XML schema, which is created by whoever develops the form. From that point of view, XDocs is a hybrid tool. But there's another way to think of it: as a structured authoring program for XML. And what that does is turn Office 11 into a pretty powerful application development platform.
For a much longer account of XDocs/InfoPath, see the interview with Jean Paoli, one of XML's creators and one of the designers of XDocs, on Microsoft's PressPass site or take your pick here.