Here is the press release which was issued by HHS.
Each state will have it’s own Health Insurance exchange up and running by 2014 to allow individuals and small business to shop for Health Insurance. There are a variety of styles of exchanges. Most models will give the consumer the option of using a broker. The HHS guidance is supposed to set up minimum rules for the exchanges, while giving some flexibility to the state to have an exchange which meets their market needs.
Here is a link to the proposed rulemaking on exchanges. You can find the section on agent/broker involvement on page 193 (Section 155.220).