Haven't blogged here for a while, so I thought I should mention for the record that I think this is a development of world-shaking importance, in order to in future gloat about how precient I am.
When we started our business the key priciple was getting useful free technology into the hands of as many people as possible. In practice we've found that everybody's needs are different, and the process of fitting the technology to those needs is labour-intensive and therefore expensive, and excludes the majority of people we hoped to help. Drupal installation profiles should go some way towards providing multiple starting points that are closer to the end point of the development process for a wide range of users.