I got an email today asking if I knew anything about slowdowns in iPhoto due to bloating of the Library.iPhoto index file. I hadn’t heard of it before, but Eric Lindsay, J Kevin Wolfe and the MacInTouch iLife reports have a lot of good background information.
My iPhoto is slow, but not too bad compared to some of these reports. However it does make using it not particularly enjoyable. My Library.iPhoto file is only 35mb (264,395 lines for 10,000 images), iPhoto takes about 15-20 seconds to show photos after launching. Most of my photos came from Sony cameras.
Maybe some of this will be addressed by the new 10.4.3 update.