Twitter has been broadcasting for quite some time that it would be making changes to the API that developers use to access it for apps and today the company is finally beginning to detail what those changes are. First and foremost, developers who create apps that perform traditional 3rd party Twitter client functions (like Tweetbot) will be limited to 100,000 users total before the developer must get “permission” and/or “work with [Twitter] directly.” Current apps will be able to continue to function as normal, however once their “user tokens” double whatever they are today, these new restrictions will apply. Essentially, once any 3rd party app hits its user limit, the developer will need to have a “come to Twitter” moment at which something will happen, and the most likely scenario is that the app simply won’t be able to take on more users.
In essence, twitter wants to control the twitter experience for the end user, and cut out 3rd party developers who create new clients who may or may not mimic the current UI, or may make it better. Of course, they also want to make sure that the display is strictly controlled, as noted by Gruber in the display guidelines. This will of course mean that twitter won’t be letting any clients that do things like say, remove “promoted tweets”, slim down the rapidly-getting-bloated web UI, or do things like create a better twitter UI.
In their rules for the number of clients, they are also essentially limiting the max amount of money that a developer can earn making a twitter client (100,000-200,000 * $
A bold move, lets see if anyone but the geeks and developers care or not. Interesting that they do this right on the heels of paid twitter alternative app.net getting funded.