Tartakovsky's Grievous was awesome. That character ended up being such a disappointment in the film. But I still liked how they tied that series straight into the final film.

I was at a talk with Tartakovsky a long time ago. I don't remember all the details, but he said when they first got their descriptions of Grievous from Lucasfilm, they didn't have much to go off of. Lucas said Grievous had a cough and that was it. Tartakovsky's team didn't know why he had a cough, so they created the Mace Windu scene.