Right, and you have to be logged in through OAuth to get anything out of the API (As far as I can tell, please prove me wrong though), which really diminishes the value you can get out of the platform as a third party.
OAuth requires a user to be logged in, which is fine if that is the type of service you are running. If you want to search LinkedIn like you might twitter, you are out of luck if you want to do it through the API. And even if you do have a service that OAuth fits, the TOS is scary enough to avoid it.