I wasn't terribly disappointed, and glad that they seemed to be trying to be subtle in the conversion, I think. And, it's a good movie, it holds up well, unlike the sequels. There are some good moments where they just pause to go "Holy Crap! Dinosaurs!" before resuming the plot.
I read a recent article on the making of it in "Entertainment Weekly," and Sam Neill said that, in the scene where they come across the triceratop under sedation, no one was "acting," they were all just reacting to the amazing mechanical props.