[Dan Newton]2. can I import FP7 work files into FCP X or is that not possible?
That is currently not possible.
3. Will Magic Bullet work for FCP X or do I need to buy an upgrade for magic Bullet?
Plugins for FCP X from Magic Bullet are said to be in development, but they have not been released yet. I'd be willing to bet that we'll see them released near the end of the year if they didn't get the SDK until after FCP X was released.