Of course I haven't seen it yet but iPhoto sounds exactly like what I need. Steve is right, digital photos are great but as soon as you attach the camera to your computer the experience falls apart.
I used to carefully rename every photo and put them in directories organized by "roll". Now that the mac has such a nice preview function I don't bother to name each photo anymore. However, I still have 200 or more pictures names abc1234 in the same directory. I think iPhoto is going to better my digital camera experience. Also, as far as I can tell, it's going to be free.
BTW, the new iMac is great for both technical and visual reasons. I want one.