Here's a great video interview on ARCast TV from some colleagues of mine at Robert Bosch (David Dickinson and Davie Sweis).  The video is about how this internal group has been evolving their SOA strategy, and how that works practically in a Microsoft centric world.  There is some mention of the Agile practices that this group has been utilizing (my group works in parallel with them and we use similar methodologies).  David Dickinson group has done some great work on SOA in an enterprise environment, this is worth a listen in my admittedly biased opinion.