No it's not. It's pressure sensitive and about as fast or faster than a trackpad with movement. I've never had a problem with speed, even across multiple, large, monitors.
On my thinkpad, I use the trackpoint and trackpad equally.
Sadly every non-IBM/Lenovo trackpoint I've ever used is awful (although significantly improved by putting a Thinkpad cover bit on the joystick, if you're stuck with one).
That said, having played through the SC1 campaign with a trackpoint... even the best ones are not as good as a real mouse.