Here's a cool drawing of the changing perceptions of those odd therizinosaurs by Tricia Arnold, a cartoonist with a heavy paleo-influence. Tricia seems to share my interest in the way artistic conceptions of extinct critters evolve as new fossils come to light. Evolve, get it? Science joke.
Here, she looks at three views of therizinosaurs that have been put forth as paleontologists tried to fit the existing fossil evidence into the dinosaur family tree. First, the "predatory prosauropod," that rather docile looking, almost sloth-like fellow in green and tan. Next, Tricia uses an idea inspired by the Dino Crisis video game - a nasty, blood-thirsty carnivore. Finally, she presents our modern idea - a largely herbivorous, pot bellied, bird-like oddball. Check out more of her artwork at flickr.