I was trying to steer away from the remote control because you have to engage the shutter release from in front of the camera and put an eye piece cover in the viewfinder to prevent light from getting into the viewfinder....and remote batteries.
Either way you have to cover the eyepiece, since that is a metering thing...
Also, you don't have to stand in front of the camera for it to work, the IR will bounce off of objects nearby the camera just fine... mine works well as long as there is something near the camera.
As far as the batteries go, yea, it does take a $2 battery but I have had mine for almost a year and have taken hundreds of shots, and still am on the battery that came with it.
There is no actual release cable made by Nikon, and I have never heard of a third party one... there is also no remote triggering port, so I am thinking it is the wireless remote or nothing.