I could not live without multi-touch now. It is a true mouse killer. I am sure it has added 30% to my productivity alone. Someone turned me on to BetterTouchTools and the rest has been history. With 3 finger click copy, 4 finger click paste I can blaze through a lot of tasks.
I love multitouch, but keystrokes are so much faster than using the touchpad.
Sure it depends on what task I am trying to accomplish, I should have prefaced that. If I am in the IDE I use the keyboard. But, if I am doing tasks like managing files I tend to use the pad.
Even for copying files, the keyboard is often quite a bit faster. Especially if you take the time to learn bash well.
I prefer the finder to the shell for file management.
And the joy of OS X is that you have both a polished GUI and a solid shell.
I love my TrackPoint -- zero-click copy (just select some text), one-click paste (middle-button).