Here on Asus P8P67.
Had to install from Realtek site on 11.04 Ubuntu, worked fine after that.
Now updated to 11.10 Ubuntu (beta 2, version available 30 September),
and booted up with no network connection!
(luckily had another system for network browsing).
The Realtek compile/install script needed some patching, because of the
kernel version number change, but after that seems to work.
Here on Asus P8P67.
Had to install from Realtek site on 11.04 Ubuntu, worked fine after that.
Now updated to 11.10 Ubuntu (beta 2, version available 30 September),
and booted up with no network connection!
(luckily had another system for network browsing).
The Realtek compile/install script needed some patching, because of the
kernel version number change, but after that seems to work.
I would consider this issue serious.