Interesting. We had a very similar experience with Technorati in 2007. We were working on a system for controlling pingbacks based on the "authority" ranking that the pinging site had, and we wanted to use the Technorati "authority" rankings. We wrote to them many, many times, using the official contact page, we offered to pay them, and then, we heard nothing. Getting desperate, we tracked down the company email addresses of some of the people who work there, and wrote to those. And we still heard nothing. We came back to the idea 3 months later and wrote again. And again we heard nothing. We came back to the idea 5 months later, and wrote them again, and again we heard nothing. When a company says "Commercial use of our API requires payment" and then you say "We would be happy to pay, please send us an API key" and then they do nothing, then you can tell that company has abandoned their API effort, but they've forgotten to take it down. And that leads to frustration.
