I do not expect every software title to be ported to ARM, nor do I expect people to run out and buy an ARM-based Mac to run their high-end software, but there is a lot of software that can be ported. Maya, Modo, and other titles like those are ones that I do not expect to get ported to the ARM architecture.OSX running on ARM is only half a solution. You also have to consider all the 3rd party applications that are commonly used on a Mac, like Photoshop, Pixelmator, inDesign, FCPX, Maya, Modo, etc. etc., and so on. How long would it take developers to port their higher end programs to an entirely new architecture? Would people be willing to put up with their absence in the interim?
I do not think Apple will release FCPX for ARM, but I do see them releasing a front-end application that lets people edit video on their Mac while the Mac Pro does the processing in the background.