It is a strange feeling that Windows 7 has "just" gone GA given that I've been running the betas and had access to the RTM builds.
However, this is also resulting in most of the vendors getting around to getting updated drivers out so you don't have to use the Vista ones.
HP released the "full" edition of the drivers at their download site for the CM2320fxi for Windows 7. At this time, there was not a 'drivers only' download. Unfortunately, the setup executables that walk you through installing the printer can't actually find the network printer: neither the DNS name nor the IP address of the printer works.
The workaround is simply to manually extract the exe file using something like 7-Zip and then use the Windows 'Add Printer' process. Annoying but it looks like everything works fine after that. As a plus (or not, depending on your point of view), the other HP stuff isn't installed (order supplies, etc.).
One amusing thing that happened was that I didn't "cancel" when the installer was running the first time before going to 'Add Printers' in windows. I was able to add the printer just fine and it was only later that I noticed the installer was still running behind some windows. Clicking cancel started the install back-out process. On the plus side, the back-out process removed everything it tried to install; unfortunately for me it did 'too good' of a job cleaning and removed the printer I installed. I guess it is like grass: it grows great where you don't want it to but won't grow where you want it to.