Hey, typically you probably wouldn't want to generate the above URI manually. We abstract how it's built through the use of the MySpace container -- you can get more details by going through the Learn & Play --> OpenSocial JS Library link. That should give you an idea of how to get back image data for a user.
Here's a javascript snippet that'll fetch the viewer's albums:
var container = opensocial.Container.get(); // gets the container object
var request = this.container.newDataRequest(); // gets a request object
var newReq = this.request.newFetchAlbumsRequest(opensocial.DataRequest.PersonId.VIEWER, param); // creates the album request
this.request.add(newReq, opt_key); // adds the album request to the queue
request.send(gotAlbums); // sends the request off and passes in a callback function
gotAlbums:function(response){
if(!response.hadError())
alert('got back an album!' + response.get("VIEWER_ALBUMS").getData().asArray()[0].getField(MyOpenSpace.Album.Field.DEFAULT_IMAGE));
}
Chad