I guess it depends on the context, timing and phase. Most often, I’ve observed that we approach the service as part of a specific launch effort. Then post-launch, evaluate the relative success of the project and evaluate whether we’re ready to take on additional partners depending on several factors like engineering cost, performance of existing partners, frequency of use by users and in tweets, other efforts at the organization, long-term goals or technology plans, and so on.
Lots of factors involved in other words.
Right now, I don’t believe we’re openly adding additional partners for these kind of on-site integrations but that certainly can change in the future.