Apple released updates to Final Cut Pro, Motion 5, and Compressor 4 today. They seem to be bug fixes (thank goodness!) My suggestion is to update very carefully. First, backup. Yes, everything. Also make sure any plugins or 3rd party effects are not affected- you'll have to check to see if the companies who make them are ready or if they also need updating. Second, quit all the apps place them in your Applications folder into a folder of their own. Then, Control-Click (Right-Click) and choose Compress. The older versions are now saved in a zip folder and you can go ahead and delete the parent folder, and empty the trash. Then, go to the App Store under Purchased and re-download them once you're signed in with your Apple ID you used to first purchase them with. This will download the latest version, and you now have the older version backed up- just in case. 

I never recommend updating right away on a machine that makes you money. Go slow- your clients don't care what you do, as long as their product ships on time. 

I hope this helps you, if you have any questions, feel free to contact me. 

Jon Belew