Instead of keeping direct competition between the three efforts going on, hoping that one would win and replace the two others, a better path became necessary and possible. Being close to the main actors of this story and building tools such as Restlet Studio that support both OAS and RAML and listening to our users, I realized that the ideal would be to have Apiary and MuleSoft join the Open API Initiative and contribute step by step to the convergence, not necessarily the merging, of the three specifications. On the API testing front, there are similar standardization needs, but beside the HAR (HTTP ARchive) format, only proprietary formats are available such as Postman Collections or JMeter Scripts.
Read the full article on the Restlet blog.
Note: Restlet is a founding member of the OAI and has recently joined the RAML workgroup.