Have you considered reaching out specifically to small businesses who are doing Twitter marketing? Maybe even within your city or state could be a good start.
A demo page would have been nice but I went for it anyway. I applied this to an internal app at work and it went to a 5/10 to 8/10 with about 45 minutes of work. It's really nice for us not-so-good-at-designing types.
It was a good interview with him. I just wish they would have asked more substantive questions about his project. I guess it is a tech show and was very short.
Admittedly, the organization is quite arbitrary. I wanted to have what I thought would be the most popular tabs up on page load, to reduce the number of AJAX requests and secondly because that's mostly what people want to read. For the tech page I thought more people would be interested in reading Digg, rather than PC World or CNET so I moved Digg to occupy a first position in a different box.
What I tried to do was split by section, then within each section split by source type. Some work better than others but for example the tech section is split mostly by social media, primary sources, e-zines (sort of), and major blogs.