Do they still ship with unusable trackpads (that requires you to carry a mouse everywhere if you ever going to use your ThinkPad) or has that improved in recent years? It's the only pain point against ThinkPad for me.
I think the trackpads are good (I mainly use the keyboard so I prefer the smaller ones over Apple's, because the keys are reachable more easily) What is it you don't like?
It's hard to describe why Apple's trackpads are better, they simply are. If you are used to them, every other one simply feels clumsy. It must be a combination of the surface (friction), the sensor (precision) and the software drivers that makes them special. I think it was when they introduced the unibody Macbooks that the trackpads became so good. The old plastic Macbook trackpads where vastly inferior in comparison.
Too small (I have fat fingers) and low sensitivity compared to the one in PowerBook (back then). This is from a company-issued laptop four or five years ago, however, I don't know if it has seen any improvements over the past years. (Especially the "too small" part.)
I've got some stubby little fingers, so much that my guitar coach in high school told me I should quit and become a bassist (a few years later I invited him to a show so he could eat his words). I use a T61 and I love the tiny trackpad. Granted I use a trackball with it, but on my home laptop with a giant touchpad, I have to move my hand to get all the way across. On the T61, I just move my finger. It feels more precise, I think. I feel like a surgeon with a scalpel.
Granted, this is just my opinion, and when I put it down into words I realize how ridiculous it sounds. But I still prefer it.
