DarkHorizons
posted the following article from the official Star Wars website:
"Though
the extremely complicated CG model of him [Grievous] is finished and
approved, his final painted form has yet to be rendered. The image
of him that graces the cover of the latest official UK Star Wars fan
magazine and the soon-to-be published official French magazine, which
can be found in the current issue of Cinefex isn't a finished form.
The long lead times of print publications required that image of Grievous
to be completed over a month ago, and Grievous has continued to evolve
since then. That image is actually a combination of an unfinished
render with 2-D digital paint applied by Concept Artist Alex Jaeger.
Grievous
has yet to make an appearance in a finished Episode III shot. That's
not to say the computer-generated character isn't getting a workout.
Already, animation of Grievous and Obi-Wan Kenobi engaged in a bare-knuckle
brawl (if something with metallic fingers can be said to be bare-knuckled)
is being developed and approved. Producer Rick McCallum says "There's
still work left to do on him before we can add him to shots. It's
not until we have a voice for him and can record a guide track for
him next month that we can really start animating his character"."