I do think you're right that it's important to _act_ and not talk, but I don't think dismissing talk altogether is productive. I don't think that HN is the appropriate avenue for social change either, but social sites are sort of the contemporary equivalent of the town square, which is where social change _used_ to come from. In order to organize political action, talk needs to occur, and it needs to happen in a place that is public so as to attract passers-by.