The category view in the BE is almost useless when you have a few hundred categories with a lot of text & images in the description.
This quick fix brings back the view from VM1.x (without the tooltip)
Change line 212 in administrator/components/com_virtuemart/views/category/tmpl/default.php (VM v2.10)
From <?php echo $cat->category_description ; ?>
To <?php echo substr($cat->category_description,0,60); ?>