At the specification level, the W3C Forms working group is working on modularization of XForms as one means of promoting incremental adoption. This is following the simple business axiom that "embrace and extend" is economically preferable to "rip and replace". If you have existing web applications, and you want to start incorporating selected features of XForms to get at certain benefits, it helps to be able to get at just those features without having to change your entire application over to XForms in one development cycle. Modularization supports agile development.
The Forms working group is now also working on XForms 1.2, even as XForms 1.1 continues toward full W3C Recommendation status. In XForms 1.2, the second approach the Forms working group is using to promote incremental adoption is to stream-line web application authoring through emphasis on attribute decoration and exploitation of UI element nesting as a means of expressing the simpler classes of MVC applications. The attributes are attached directly to UI elements, but they imply a proper XForms MVC architecture. In other words, the XForms processor can read the attributes and auto-generate a proper model for you. To get an idea of what the stream-lined vocabulary might look like, and what canonical XForms it might correspond to, look here.
The approach of providing stream-lined syntax is simpatico with modularization for two reasons. First, it means we can provide the stream-lined vocabulary and processing model as a module separately from modules that provide the components of the core XForms engine (e.g. the instance data module, the submission module, and so forth). Second, the stream-lined syntax approach means that authors can start with attribute decoration and UI nesting, and then scale up in more complex functional areas as the need arises by adopting the core XForms modules appropriate to the problem at hand.
The stream-lined syntax approach is also interesting because techniques such as attribute decoration, UI nesting, and progressive elaboration of a document are techniques familiar to AJAX developers and made popular by AJAX libraries such as Dojo. In fact, I am really coming to the conclusion that AJAX libraries are a viable alternative to browser-maker adoption as a means of delivering the most web-centric components of the W3C technology stack. It should not be necessary for Microsoft, Mozilla, Apple, Opera and other browser makers to build a W3C technology into their browsers before it becomes widely adopted and deployed. More importantly, this means that the W3C, not the browser makers, defines the web and its standards.