It seems like a good start, though a little confusing at in some places.
One consistent problem was a tendency to just tell people to do something, but you don't explain why. This could especially cause problems when you setup something that isn't really needed by many people and could be considered against the Arch Way
Some specific things that jumped out at me:
Under the needed hardware why do you say no laptops? Arch runs fine on many laptops.
The download instructions was confusing, you say which directory in the mirrors to use (which is now outdated) before you link to any mirrors. I could imagine a new reader wouldn't know what the first part was referring to. It also would be worth mentioning the availability of torrents.
I'm not sure why you suggest having another liveCD and downloading the pacman and midnight commander packages separately.
I was confused by the instructions to use /mnt/repos. If a network connection is available this isn't really needed, but you don't explain why you're doing it very well at first.
You assume people should use the cd install, but should probably at least mention the possibility of an ftp install since that will give more up to date packages if it can be done and save time updating after the install.
lo isn't needed to be included in /etc/rc.conf anymore. Also you give instructions for using a static IP, but I figure most people would use dhcp, especially if they don't know what they're doing.
Why aren't you configuring fstab during the install? Doing it from within a separate liveCD seems like an unnecessary extra step.
Similar with Xorg, why not wait until you boot into Arch, install the Xorg packages natively, and use those tools to create the xorg.conf?
If you do want to merge parts into the wiki a good place to start might be to add things that might be missing from the beginner's guide