As mentioned previously, Premal Shah of Kiva.org recently spoke at the PARC's special speaker series on "Going Beyond Web2.0". During the talk, Premal gave many great stories of how Kiva got started and the growth of the system. It was a great talk, because it showed that Web2.0 can be used as a way to connect people directly and to help them to get out of poverty. The way Kiva.org does this is through microloans.
The key, according to Premal, is transparency. At the talk, he said, "The reason why people dig Kiva is because of the transparency." This coincides with our "social transparency" principle that went into the design of WikiDashboard---we make the data visible and easier to understand, and you decide on how to use the information. Premal used the same principle here in the design of Kiva. For example, he said that they expose on the website the risk rating of various microloan organizations, and it is up to the users to decide on how much risk they want to take with their loans. The idea here is that a "social investor" in microloans need all of the information and make the decision locally in a distributed way. If enough people votes with their $25 loans, then a higher-risk loan can still get funded. Indeed, "people funded $25 at a time can actually beat Citibank's $100M microfinance total fund."
Incidentally, Katie Payne, who is giving the PARC forum on how to measure social media effects, is just now talking about the importance of "transparency" in building credibility and trust.
In any case, here is the Premal's Kiva talk: