Here is an interesting example of how to visualize the Discussion arenas:
Here is one example of a Discussions arenas, where People are willing to speak or discuss:
TheGapminder just released Trendalyzer - OECD Factbook 2008. Trendalyze - Classic is still available. Many Eyes has a forum for OECD Factbook 2007.
Combine the Discussion arenas, Easy access to facts and Visualizations of the effects*, and you will have a powerful Lobby machine.
*The Effect can viewed in the Presidential election chart, under Trends.