From what I can tell this is a bug.
This is how I fixed it.
1. Open iPhoto-Preferences-general
2. Where is says "Connect Camera Opens" it should say "No Application" even though the aplication still opens. If it doesn't switch it to no application. If it does go to step three.
3. Set it for whatever program currently opens. (iphoto or image capture)
4. Save the preference and shut down iPhoto and Image Capture
5. Dissconnect the camera
6. Reconnect the camera
7. Open iPhoto-Preferences-general
8. Where it says "Connect Camera Opens" change it from iPhoto or Image Capture to "No Application."
9. Save the preference and shut down iPhoto and Image Capture
10. Disconnect the camera
11. Reconnect the camera
The problem should be fixed at that point. You basically need to reset the command.
It worked for me. YMMV