RAD on OpenSocial

We started with OpenSocial around mid of February. After 2weeks of learning about the API, its basic how to's and running simple samples along the way with errors and headaches. Having MySpace developers forum and irc channel really helps. Getting answers from the MySpace Dev team and 3rd party devs.

First thing first is having a sandbox access to social sites or the container which supports OpenSocial, like MySpace dev sandbox, Orkut, Ning, Hi5.

MySpace took me 3 days to have an access to their dev sandbox, while in Orkut only one day. I later found out that my application for sandbox access wasn't approved for they want more info on me, making sure that the access is given to a real developer and not just spam boots, well enough of that.

For it is a sandbox access your application can only be added to at most three users (now they changed the limit to 20 users) who are friends of your application (for security purposes) so, you can not just add millions of users or anyone on MySpace. Every application you create has a separate MySpace Accounts. So every application has a different set of friends.

MDP has its own application builder and Caja test tools (which they currently removed).
Applications can either be a pure html or js, a flash app, or an external IFrame. Since they currently don't support REST APIs you need to host your apps data. Since not all fields are in the OpenSocial API, MySpace extends those APIs.
As of now OpenSocial's Activities and Data API's are not yet supported.