Does anybody have the exact process name for the 10.10.1 installer that would allow me to restrict that while still allowing the base 10.10 installer? We need to prevent people from installing 10.10.1 while we do our standard testing to make sure it's not going to blow anything up.
Use Restricted Software to block Yosemite. Users will still be able to upgrade using Self Service if you've made it available there. Don't add the 10.10.1 copy of Install OS X Yosemite.app to Casper Admin until you're ready.
Blocking the update should be easy if you are using an internal software update server.
Edit: The process you want to block is *Yosemite* and do not check "Restrict exact process name."
Looking at the man page I think -i tells software update to install the update. To ignore it you use --ignore.
My Mac App Store is connecting to a23214-64-56.deploy.static.akamaitechnologies.com (from the UK) so it might be pretty tricky to pin it down by blocking URLs.
Not a technical solution but I would probably send out an email to the users advising them not to update to 10.10.1.
The process is actually called InstallAssistant
If you just put *Yosemite* that is not the binary process name and users will circumvent it by just renaming it.
 putting a restricted process on InstallAssistant will stop both 10.10 and 10.10.1 mind and its a difficult thing to accomplish whilst stopping users rename it