In 90 minutes, Garg, Matt and David built a working web photo sharing web site.  Garg played customer.  David played whip-cracker (um... PM), and David did all the heavy lifting with Rails.

This talk was a high level introduction to the speed and power of Rails as a development environment.  As such, I found most of the material repetitious of other demos I've seen.  But, the guys did a good job of showing off the Rails notion of "convention over configuration."  They also showed off RSpec and demonstrated the plug-in architecture.

Recommended resources (from Garg, Matt and David):

I would have liked the session to be more hands-on.  I'll have to check out the Rails lab for that level of immersion.