Twitter has recently released a new set of developer guidelines. There was also a statement from Twitter’s platform/API leader, Ryan Sarver: “Developers ask us if they should build client apps that mimic or reproduce the mainstream Twitter consumer client experience. The answer is no.” This would make Twitter less like a platform, and more of a product.
Building a business based on someone else’s is always a risky position, especially should they become a little unpredictable. For instance, to take a completely random example, if they are still trying to find a way to generate revenue, or if their interests and yours suddenly diverge.