I'm setting this via Casper Managed Preferences (MCX) and it's working well. See the following...

https://jamfnation.jamfsoftware.com/discussion.html?id=4920

For whatever reason, I had previously chosen not to go the MCX method...I'm guessing it has something to do with me wanting to manage 10.7 and 10.8 with profiles and only use MCX for 10.6, but anyway, I built a DMG package that will suppress the Setup Assistant (at least as of 10.8.3).

To do that...what I did was to craft a plist file named com.apple.SetupAssistant.plist with the following:

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">

<plist version="1.0">

<dict>

    <key>DidSeeCloudSetup</key>

    <true/>

    <key>LastSeenCloudProductVersion</key>

    <string>10.8.2</string>

</dict>

</plist>

Once you have the plist created, you then have to make sure that the plist gets down to the User Template under preferences. Casper handles that with the "fill user template" option. You could also copy it to existing users, but I'm guessing if a user has already logged in that this step would not be needed. I'd be happy to help more if you have questions on this method. I'm guessing the MCX method would have been fine as well...not necessarily knocking it...I just wanted to avoid using MCX.

Thanks blackholemac!!!! That was super useful!

I was never able to get the MCX route to work with my machines. Instead I have a script that runs on startup to move /System/Library/Core Services/Setup Assistant.app/Contents/Shared Support/MiniLauncher to MiniLaucher.old. MiniLanuncher being that actual application that shows the iCloud login screen.

Beware the MiniLauncher rename hack. I applied it to 10.8.2 machines, and it promptly broke Setup Assistant after an update to 10.8.3. I was seeing a gray screen after login, which was caused by Setup Assistant crashing. I had to load in a fresh copy of the Setup Assistant to bring back normal functionality.

Also you can run this Post Image script at imaging time.
Script Priority: At Reboot

# Disables Apple ID pop-up on first login for Macs running OS X 10.8.x

# Apple ID setup pop-up in OS X 10.8 for new users by setting com.apple.SetupAssistant in

# /System/Library/User Template/Non_localized/Library/Preferences/ 

# to include the key "DidSeeCloudSetup" with a Boolean value of TRUE and LastSeenCloudProductVersion with OS version

#



osver=`sw_vers -productVersion`



/usr/bin/defaults write /System/Library/User Template/Non_localized/Library/Preferences/com.apple.SetupAssistant DidSeeCloudSetup -bool TRUE

/usr/bin/defaults write /System/Library/User Template/Non_localized/Library/Preferences/com.apple.SetupAssistant LastSeenCloudProductVersion $osver



exit 0

Interesting…I had no issue with the MiniLauncher move when I upgraded to 10.8.3. Here is the code I use:

#!/bin/bash
if f -f /System/Library/CoreServices/Setup Assistant.app/Contents/SharedSupport/MiniLauncher ]; then
mv /System/Library/CoreServices/Setup Assistant.app/Contents/SharedSupport/MiniLauncher /System/Library/CoreServices/Setup Assistant.app/Contents/SharedSupport/MiniLauncher.old
fi