Joel Burslem of 1000 Watt makes a very important distinction between intent and result.

Original Zillow thinking:

“REALTORS® currently sit at the middle of transaction. I think in the future they will sit more on the outside, offering specific services… People want REALTORS®, but is it rational to pay REALTORS® what they are paid? They are overpaid because customers are doing more of the work themselves. What kind of value are REALTORS® adding?”

Rich Barton, CEO Zillow - New York Times 2/9/06  – 2/8/06

1000 Watt Article