Automattic/WPCOM-Related-Posts — pull request #12 by andrewryno (2013-03-26 19:21:23+00:00)
Title: Allow thumbnail size to be filtered for custom image sizes

Should be pretty self explanatory. Difficult in the theme to make sure the related images are all the same size. The size is different than the normal post thumbnail size (in my theme and I'm sure others as well), so the `post_thumbnail_size` filter would affect more than just the related images.