I did a clean install of Tiger on my PowerBook G4 (1 Ghz, 768 RAM, Giga-ethernet Titanium) and it resulted in the following bugs:
The F1 and F2 keys no longer function to control Brightness Up/Down.
In Display Preferences, only one resolution is available: 1280 x 854. Furthermore, there is no brightness slider to control monitor brightness.
In iTunes, full-screen visualization does not work.
Other PowerBook owners have reported identical problems in the Support Forums:
http://discussions.info.apple.com/webx?128@940.tPYFapKBQqr.8@.68adc304
Finally, this feedback form does not have 10.4 under 'Select OS Version'
P.S. I should mention that I have done the following in an attempt to remedy this:
a) Repaired Permissions
b) Booted into single-user command line and did 'fsck -yf'
c) Reset the PMU
d) Reset the PRAM
e) Reset the NVRAM
f) Deleted the com.apple.displays plist
g) Created a new user account and logged in from there.
f) Did a second clean install. The problem remains.
A user in the forums reported that when he booted into Panther, his keys and resolution returned to normal functionality. This is most definitely a Tiger problem.