During the PI refactoring I found the TAO_ORBInitInfo_var in tao/ORBInitInfo.h.
It is just for the following:

It is there so that users can do the following in their ORBInitializers:

 TAO_ORBInitInfo_var tao_info =
    TAO_ORBInitInfo::_narrow (info
                              ACE_ENV_ARG_PARAMETER);
  ACE_CHECK;

  if (CORBA::is_nil (tao_info.in ()))
    ACE_THROW (CORBA::INV_OBJREF ());

  // SSLIOP doesn't use the ORB Core until a request invocation occurs
  // so there is no problem in retrieving the ORB Core pointer in this
  // pre_init() method.
  TAO_ORB_Core *orb_core = tao_info->orb_core ();

The narrow could be a dynamic_cast, that works now, but the ORBInitInfo also has
in the latest spec a get_orb() which can then be used, but this is not
implemented yet.

This TAO specific extension has to be removed in the future