gotcha... if you want to test the cord, open iphoto, with the camera attached and the camera ON... iphoto will see the camera, whether your using raw or jpeg... if that see's it, then the cord is good. If it doesn't, then it wont. Also it may sound silly but if you have the camera connected but it goes to "sleep" mode, then the computer wont see the camera. If iphoto doesn't even see the camera, then the cord you have is duff.
edit... keep in mind, iphoto cannot import raw files from the camera, only jpegs, BUT you will physically see the raw pictures previews.... That will tell you the cord is or isnt working the way it's supposed to.