a story from the Radio and Internet Newsletter (RAIN) quotes former Broadcast.com CEO Mark Cuban as saying that the Yahoo!/Broadcast.com/RIAA streaming royalty rate deal was specifically structured to the disadvantage of small-scale webcasters.

by adopting a per-song/performance rate, rather than a percentage-of-revenue model, only the deep-pocketed could survive. like Microsoft's long-time policy of charging PC makers a Windows royalty on every box sold (regardless of whether or not it shipped with Windows installed), it served to create a huge barrier to entry for competition. according to Cuban:

I...wanted there to be an advantage to aggregators. If there was a charge per song, it's obvious lots of webcasters couldn't afford to stay in business on their own. THEREFORE, they would have to come to Broadcast.com to use our services because with our aggregate audience...we could afford to pay the royalty AND get paid by the webradio stations needing to webcast. [emphasis is Mark's]

so the marketplace deal used by CARP and the Librarian of Congress as the archetype for the new webcasting royalty regime was essentially designed as a scorched-earth policy to starve smaller, less-well-funded webcasters of revenue.

mission accomplished.