The rest of this posting is really for Googlers trying to solve upgrade issues from Dapper to Edgy, and also a little Beryl guidance. Welcome, visitors!
After I upgraded using apt-get distupgrade, my system failed to boot into the new kernel. If you are booting and it seems to hang, wait three and four minutes, and you may see something like this:
ALERT! /dev/disk/by-uuid/ed4395c8-e15c-4b20-8716-76ceff89614e does not exist. Dropping to a shell!Don't panic. Since you're upgrading, you still have your old kernel you can boot into. Boot it, change to your /boot directory, and do this:
BusyBos v1.1.3 (DEbian 1:1.1.3-2ubuntu3) Built in shell (ash)
Enter 'help' for a list of built in commands.
dpkg-reconfigure linux-image-2.6.17-10-generic(use the same name suffix, e.g. "2.6.17-10-generic", as the new kernel you upgraded to). This command builds you a new initrd image file, and you will be able to boot.
My second issue was particular to my laptop, a Dell Precision M70 with an Nvidia card. You really need your Nvidia card to work if you're going to use Beryl. Something in my default upgrade linked to the latest Nvidia driver (1.0-8776), but that driver did not come in the upgrade; X failed to start. Thanks to Alberto Milone for these excellent notes on upgrading the driver without disabling your wireless card.
I had a fair amount of trouble getting Compiz/Beryl to work. I had tried Compiz on Dapper, and never got a working install. After upgrading to Edgy and getting it stable, I investigated Beryl, and had similar trouble: Lots of garbage bits on the screen, windows with no titlebars or borders -- unusable and depressing.
Finally I fixed all my problems by twiddling my xorg.conf. Here are the relevant twiddles (ymmv):
Section "Device"
Identifier "NVIDIA Corporation NV41 [Quadro FX Go1400]"
Driver "nvidia"
BusID "PCI:1:0:0"
Option "RenderAccel" "true"
Option "AllowGLXWithComposite" "true"
Option "Triplebuffer" "true"
Option "AddARGBGLXVisuals" "True"
EndSection
...
Section "Screen"
Identifier "Default Screen"
Device "NVIDIA Corporation NV41 [Quadro FX Go1400]"
Monitor "Generic Monitor"
# depth had been 16:
DefaultDepth 24
...