Standing in between someone and the information they need...
is a sure way to lose a job. Jeff Jarvis, in his excellent blog Buzzmachine recently commented on the Justice Department’s antitrust settlement with the National Association of Realtors. He rails against the market inefficiency created as realtors monopolized listings. He goes on to point out that 6% commissions are a thing of the past as internet brokers will now be able to compete on a level playing field.
It brings to mind a comment that a b-school professor made to me years ago "Never stand between someone who needs information and the information itself as you'll soon find yourself out of a job". So far I can only think of examples that by and large support this theory. For example, when financial data became more ubiquitous, the role of stock brokers changed drastically. The same is true for travel agents thanks to websites like Expedia, kayak.com and travelocity.
However, it is important to note that just because some inefficiency or monopolistic profits are squeezed out of a market does not mean that all those workers are out on the street. Markets have a way of segmenting themselves and the smart realtors (following in the steps of the stockbrokers and travel agents) will focus on higher net worth individuals, or corporate relocators or other high need/low time people to build their business. For the "down market", they may adopt the strategies of their internet competitors and use their strong brands to grow share.