I just read Eric van der Vlist’s excellent XML London paper, in which he discusses the (lack of) modularity in XForms, caused to no small degree by the XForms MVC architecture, and, more importantly, offers solutions and workarounds. I really should have been there.
Having dabbled with XForms myself lately, I’m now very much looking forward to his talk at Balisage and the International Symposium on Native XML User Interfaces in Montréal, later this year.