dragging into the present

I need a fcp mentor for this. I have fcp 5 and a iMacPowerPC G5 on Panther. I did one 24 minute video project and want to start another, but need to upgrade to a new Mac. My question is, for the new Mac Pro 2.66 duo core intel will I be able to keep my current software without running into problems? (It's all academic so I can't upgrade) My skill set is very minimal, I just need more space on my computer. I use a ton of photoshop images and Motion.
I'd really just like to stick to the new iMac, but I'm afraid I'd end up where I am now in a couple of years.... needing more oomph and more memory. Thanks for your time and guidance.