In the interview, Steve mentions that it's basic to loosely coupled services that object references not be passed around.
I am developing a web service that takes as it's only input param an object (just a structure, really). That way I can add new parameters to the service by adding properties to that object w/o breaking existing clients.
Am I violating this loosely coupled rule?
I think it is OK, as long as when you add new members to the structure, it still has meaning if older clients are not supplying those values. So if you add a string member, the older client will essentially be passing null for that value (since it is not present)
and you have to expect and handle that gracefully.