Gef, I was under the impression that Loosehead had answered that aspect of the question and was only attempting to add some perspective to the apparent difference in shape between a large planet and a small asteroid.
Mt Everest is larger than most asteroids yet has a distinctly non-spherical shape when viewed up close. In the context of its overall size, the Earth is impressively spherical in shape yet in many places no more spherical than an asteroid were it possible to make a side by side comparison.
My apologies to anyone I may have lead astray. As penance for my pedantry I offer this link to:
Why are planets round?