I think it might be a good idea to attach a discussion forum to every prediction market contract. I think it might allow traders to make money off of private information faster and with less risk than they can now and might increase the amount of information generated by some markets.
If each prediction market had a dedicated forum attached to it, market participants who have information not currently incorporated into the contract price could make fast and relatively low risk profits by first buying all the contracts they want, revealing their information, and then selling their shares at a profit after the contract price adjusts. This would allow people who bring new information to cash in on their information quickly and with minimal risk, and would have the added benefit of making such information or analysis public.
Attaching forums would be very easy; a link on the contract information page would be sufficient. Moderation would not be problem because traders would have to have accounts with the prediction market exchange, so real punishments could be given to those who post fraudulently.
Discussion forums would also give people who are interested in the meaning of the contract price to ask questions about the logic behind it, though I don’t know if traders would answer.