It's not so much about saving time for me as it is about avoiding the context switch. If I'm typing on the keyboard moving my hand away to the mouse or down in the case of a trackpad and then carefully positioning the cursor on the screen and clicking, is disruptive to my workflow when I just want to think about what I'm typing. For daily use I use a Trackpoint to at least avoid the hand movement, but moving the cursor around still takes me out of whatever I was doing to focus on the UI (in addition to the annoyingly persistent Trackpoint drift issue).

But I agree that Apple's touchpad gestures are awesome and from the few times I've tried it it worked much more reliably than on any other device. Still, I haven't found a more comfortable setup than a ThinkPad keyboard + Trackpoint. The insanely short key travel on Macbooks is unbearable to me.