Grader should have Identi.ca support, including factoring in those people who broadcast on both Identi.ca and Twitter. Identi.ca has an API that is identical to Twitter, so that would save a lot of time in the implementation.
i would check again, the open source community is very active on identi.ca and I am starting to prefer it over twitter, because there are not so many senseless posts
AdminYoav Shapira (Admin, grader.com) commented
But almost no one uses Identi.ca ;)