Just installed OS X 10.4 on my PowerBook G4 A15.
You need to be patient and confident: Took an hour, and three times I was looked up from my book during the process and thought ‘oh oh’ since it just seemed to get stuck. It never was and all worked.
My first impression is that it looks great. Fonts are crisper. It overall is easier on the eyes. With every upgrade the look got cleaner. OS X 10.0 was very ugly. Since there has to be something to go away in 10.5 they left one horizontal line in the middle of the menu bar. Dashboard (F12) is one of these first time usage toys, that probably will be left alone once the
novelty wears off. Which is right about now. Same happened with video chats in 10.3. Was it 10.3 ?
Downloading the 37MB 10.4.1 update right now.