Your own linked articles about that topic are a user only complaining about the legal takedown of a useful tool [1] and another complaint about UX with an included blurb asking startups and users to put their time and data into something better [2]. Nothing about API changes or right to a company's proprietary data.

[1] http://blog.garrytan.com/save-padmapper-craigslist-is-wrong-... [2] http://pandodaily.com/2012/05/30/craigslist-is-squashing-inn...