Track Pad

It is not a requirement for Lion to have a multi-touch trackpad like the Magic Trackpad. You can still use much of Lion without it. However some features like Mission Control and Launchpad work better with gestures so the IMHO the "experience" is better with gestures. So I vote to get the Magic Trackpad. 🙂

But if you do not, I would not worry about it too much. I do not plan to get a trackpad for my Mac Mini when it gets upgraded to Lion, even though I use gesturing a lot on my Macbook Pro.

As Asatoran replied, using a trackpad like the Magic Trackpad will allow use of the full range of gesture-commands in Lion. Using just a mouse will not prohibit using Lion, just will make how you use it different.

Whether you would find a trackpad easier to use than a mouse is, to a great extent, a function of you and what you are comfortable with using.

I've never found trackpads comfortable in the past. That said, I find that the simple gesture-based functions available with the Magic Mouse to be intuitive and easy to adapt to.

Note that the choice is not an either-or choice - you can have both a trackpad and a mouse available and functional at the same time, switching between the two as needs dictate.

I will probably add a Magic Trackpad to my config in the near future.

Sometimes ya gotta get in the water to find out if you like the pool.

To add to what Don said, I'm from a photographic background and prefer to edit with a mouse or tablet. I find I don't get enough precision with a trackpad. Less contorting my my wrists with the tablet. Currently, I have a trackball for general use, then switch to the tablet for fine editing. Eventually I may get the Magic Trackpad, but I don't have a complete need for one in my workflow, even with my imagined usage of Lion on that machine. Like Don said, you can use multiple pointing devices so just use whatever works for you. My guess is that you'll continue to edit in FCP just like you do now with your mouse or whatever, then slowly start using more gesturing on the Magic Trackpad as you learn more about Lion. 🙂