Sigma -
That is certainly a myopic view, but not without merit.
As in all systems, the value of the database can be measured by the quality of the data, and a fair amount of this MLS is bad. The VOW policy liberates the listings far more than the IDX policy; however, you still have agents on both sides of the deal, and either is subject to self-serving behavior (as is constantly borne out by the disparity in the Realtor-as-a-client reports).
Realtors manipulate the system (not just the MLS) in many ways:
Poor representation of a listing
Misleading representation of a listing
Intentional withholding of a listing from the MLS
Relisting a long market time listing
Bias based on commission
Bias based on other side agent/agency
RESPA ha-ha
... and I'm not even a Realtor -- I'm sure they can think of a few more (not that they would put them on virtual paper here).
This is also why I continue to be pro-VOW and anti-ILD. ILD would proxy the MLS into an advertising driver and, once that happens, whoever has the largest marketing base wins -- forget service, and listing fidelity would be almost meaningless. It would only further reward misrepresentation as the buyer agent is virtually eliminated from the process.
I believe the MLS was developed not to level the playing field but for Realtor convenience. While far less noble, it's far more realistic.
-Matt