Introduction

Finally the API is out. Let all the excitement come to rest.

First review of the API , in nutshell it just an google widget (existing Google Gadgets) with Javascript and Open Social API as extension.

Basics
Javascript API (released) provides basically request and response model(Ajax)

The Data API (Open Social API) provides access to the Data Model(users, profile, friends etc).
It is designed to enable developers to access two specific datasets
1- Access Users' Profile & Friends (People & Friends Data API) (Not released yet)
2- Access User Actions (Activites Data API) (Not released yet)

API Review

I think there was a need to standardize these API and this possibily looks like a right step.
But it doesn't seen as open it should. It more or less a google proprietary based on gadget.
GData is a protocol based on the Atom 1.0 and RSS 2.0 syndication formats, plus the Atom Publishing Protocol. It the Google data APIs(GData API) which has not been widely accepted as of yet but fore sure extend the ever lagging behing spec. So developers conversant with this protocol and way of development would have a head start.

The API does not look as clean as it could be. Also integration between various social networking sites and data exchange format has not been defined (At least I didn't saw it).

The Service Provider Interface (SPI) for the Gadget has not yet been defined/released so far. So companies trying to develop complaint container have to wait.

In the data API the elements of the profile that can be retrieved or updated still needed to be defined.
This set of elements would be vendor/container specific and would provide custom extensions to the api data model.

Again you have to signup in order to get access to SPI interface.
It not clear when would the Orkut Container will go live.

Building & Porting Applications

Building sample apps In the initial development, is/could still buggy.
Looking to Opensocial Forums can help a bit, but would take some time for all things to be captured.

There aren't much tutorials or help yet that provides example of all the fields that can be acessed from the profile or how various network can exchange information between each other.

One of the thing i liked about was the ease of converting an existing application into a gadget.
For most part your server side app(developed in any language Ruby, Java, Php etc) would work with a few changes. If you app has Ajax support it even easy to port.

Developing and debugging in javascript can be pain esp. when the gadget content is cached by container. For refreshing the gadget/app append &bpc=1 parameter to your application urls.
Firefox plugins like Firebug, Live Http along with traditional debug/print message to console can come to help.

The gadget/app can be initially developed and tested in the Google Gadget Editor but it does not support Open Social API as of yet. So the final testing has to be done in the container(sandbox) itself. There is no good development environment so far, so its good time for IDE compaines to build something here. Would like to see an Eclipse plugin geared towards it soon

I did not see any infrastructure as provided by Facebook to share the applications (viral).
I would expect that framework to be provided by the container. Its not there in sanbox and hope that it would be there in real one. The size of canvas for the application is also adequate the display the app in the container.

Facebook Angle
Also don't see how this would be threat to Facebook.
If they want they can extend this in no time. Facebook applications have a huge base and the number of applcations is growing day by day (over 7000). The question looming out there is will Facebook join the Open Social Wagon?