Open up the ImageCapture application and in the preferences set which application you want to start when a camera (the iPhone looks like a camera when images are present). is connected. You will set, iPhoto as the desired application. Be warned though that it will always open and be annoying when you want to use iTunes to sync. Personally I prefer manual control of both. I do not want iTunes automatically starting a sync, not do I want iPhoto to open when I might not want it to.