I have read some reviews on it.
KDE/Gnome are supposed to be more integrated now, and they both are better versions that what was shipped with RH8.
Samba and Web Server, as you said, both have a much better gui.
The package manager STILL SUCKS. Man I can't wait til they get something like apt. I know you can install it, but it would be nice to have it by default and maybe a nice gui. Of course, then there would be less of a reason to join RHN :p
Still no mp3 w/ XMMS, and now I believe Xine is gone too.
I recommend upgrading the Mozilla, read it handles installation of plugins much better, and 1.3.x also adds popup/spam controls.
Also, NVIDIA drivers are supposed to be a [censored] to get to work as of now. So I think I will wait a while.
This is all from what I read, I haven't installed it yet. So if you have more points, or corrections, let me know.Correction
: Just found this out. I assume most of ya know it already. http://news.com.com/2117-1045-994716.html
new NVidia supports RH9 and Mandy 9.1. And on top of that, they have added a linux util that will let you. Also the new util will select the correct drivers for you and install them. Sounds like they took NVchooser.sh and added a nice install. Good deal!