I have now tested Mountain Lion on 4 different MacPro Towers, and Final Cut Studio (Latest version) seems to work fine on all of the machines after doing a clean install of the OS and software. The only machine that I attempted to upgrade the install - FCP would crash immeditately after launch.
So, for the record, backing up my HD, then erasing the volume and installing 10.8 from scratch, then installing all of your software - FCP seems to work fine if it's the latest version.
**One important note: Make sure that any plug-ins you use are compatible with ML BEFORE you choose to upgrade!
Though I did not post this question... I have the same concerns.
I have FCP 7 on my new iMac. I have not made the "change" to the newer one yet. I am hesitant to up grade to Mountain Lion until I am sure that my current version of FCP will work on it (It does work fine on Lion).
If anyone else has an answer to this, I would be much appreciative!
My testing has shown that by simply "upgrading" the OS, Final Cut Studio didn't work properly. My guess is that 10.8's handling of permissions somehow makes older installs of FCP not work. (GUESSING, not fact)
However, I was OK with running OS 10.8 Mountain Lion, erasing the Hard Drive, installing a "fresh install" of the OS, and then installing Final Cut Studio. I then did a Software Update, and then launched FCP after a restart. It works fine. My machines are 8-core and 12-core Mac Pros, they all shipped with Lion initially.
Hope that helps!