The Umbilical Bros David Collins isn't actually the most famous David Collins involved in US TV. For more info on the more famous (or more successful) David Collins then go here:
http://www.ohio.edu/ohiotoday/profiles/davidcollins.cfm
And that should stop those rumours that the two David Collins are the same person! Someone swore to me the other day the the Umbilical Dave was the same as the producer Dave.