You can use this method, which I just found....But realize ANY camera you connect, you have to manually upload....Which I might just do, form here on out anyway.
pen Image Capture and go to the Preferences menu (under the Image Capture menu item). Under the General tab, change the option for “When a camera is connected…” to “No Application” instead of “iPhoto”.
This means you’ll have to manually start iPhoto when you connect your digital camera, but you won’t have to CLOSE iPhoto every time you plug in your iPhone (which, for me, is a heck of a lot more often than plugging in a camera!)
Yup, I had found that out and posted just above my other comment.
I find it odd that my version of iPhoto doesn't allow you to change that feature inside its own preferences, however....Does anyone know if that is a feature of the newest version of iPhoto? I saw examples of this in some of my searches as well. Just a curiosity.
I am glad the question was brought up....iPhoto opening up all the time annoys me too, but I am lazy enough that I chose to not figure out to find a way to turn it off. So, without this post, I would never have made the effort. Bonus for me!