Post Magazine has a short interview up with Ben Snow from ILM about the VFX used in Iron Man. They have a few interesting shots showing the multiple passes used in rendering some of the larger scenes.
Randall Hand
Randall Hand is a computer graphics programmer and news junky that's been working in the field for the last 15 years. He's responsible for visualizations generated on some of the most powerful supercomputers in the world, ytnef, mullion support in ParaView, and VizWorld.com.