When you start an architectural visualization project modeled with Blender these days, which renderer do you try to use? A lot of people is starting to move all their projects to Cycles, and it is not just because it is already there, you don`t have to install any extra software or exporter. The renderer is getting more features on each Blender release. And since Cycles is a very recent feature of Blender, all learning materials available are mostly welcome. I just found out another nice tutorial about Cycles for architecture created by blenderpedia.
This is a relatively long tutorial, with almost one hour of video showing how to setup an architectural scene with Cycles.