Twitter's decision to change the goal posts for its APIs is, in effect, stealing. After building--to its own benefit--an ecosystem that helped to spread its use, make it relevant, make it ubiquitous, and make it money, Twitter has decided to pull an Apple and screw part of its developer community.
Twitter's apparent arrogance is unfounded; it doesn't produce the best client for its customers, even on its own site. But that's not even the issue--it's that they've represented one thing for years, and are now screwing developers who depended on them, trusting them to not be Apple.
Reparations are in order. Any developer/company that has invested in building software that is now "banned" by Twitter should be repaid, with interest, for the time, effort, and innovation they brought to the Twitter ecosystem.
Now we just need a US District Court to aid in the effort, and some plaintiffs. I won't be among them; we haven't developed that dependency though we are using other aspects of their APIs. But I feel your pain.