Question to the Internetz on API usage

For the last couple of weeks with our new Magma site, we have been hitting Digg, Reddit, YouTube, Twitter, and a lot of other sites, with over 30,000 requests per day, each. For every video we track, we go out and see what’s going on on each of these sites and then continue to check back time and time again.

At 30,000 requests per website, per day, so far no one has mentioned anything.

We’d ready now to ratchet this up to 100k requests per day and foresee the desire for a million requests per day on the near horizon.

Does anyone know what is considered typical usage? If no one cares that we are making 30k requests per day, will they care if we make 100k? Are we flattering ourselves in thinking a million requests per day is significant? Will anyone care? What are good practice API benchmarks on usage levels for companies that do provide APIs?