Maybe it was too early back then to see the value in it, but does anyone remember App.net? Dalton Caldwell (now working at YCombinator) had a plan to build a backbone for developers to build on top off without fear of APIs being taken away from them[0]. The idea came about from this exact topic (Twitter becoming more and more hostile to developers)[1].

[0]http://daltoncaldwell.com/an-audacious-proposal [1]http://daltoncaldwell.com/what-twitter-could-have-been