It would appear that on Sep 30, Matthew Monaco did say that:
On 09/28/2011 01:41 PM, Ionut Biru wrote:
NVIDIA users be aware that xorg-server 1.11 from testing is incompatible with the current nvidia driver, even with IgnoreABI. You can switch to nouveau or add xf86-input-evdev xf86-input-synaptics xorg-server-common xorg-server to Ignorepkg.
I didn't see Ionut Biru's post, and actually not being a gnome user I'm surprised I opened one from this thread. But the bit about "NVIDIA users be aware" kinda caught my eye.
Since the version of xorg in question is "from testing" I suspect I've nothing to worry about and that it wouldn't wind up in the main repo while its still "incompatible". But since I know for a fact that my PC's built in Nvidia adapter is extremely incompatible with nouveau, I'd like to understand what and where this "Ignorepkg" is?