Of course, you know Viadeo. The professional social network that is known worldwide
They will open their own API on June the 28th. Stay tuned, follow their blog.
3scale is “The Easiest way to Open, Manage & Monetize your API”. In a nutshell, if you have a web service and want to open your API, you have to think about “access control”, “analytics”, “billing”… Well, 3scale provides all these services on top of your existing API.
They will give a talk during the event about the importance of APIs in the web of today.