I just updated a site using Coherence to WordPress 3.5 and it looks like the easy method in the Add Media editor to "Set as featured image" is gone. I did a search and found some other threads about this.
One of the solutions was to add one image to the slideshow and it would be set as the featured image (to show as thumbnail in recent posts widget) and not show as a slide in the blog overview or single post. This worked for setting a thumbnail, but the one added photo also showed as a slide in the blog overview and single post. What I did to correct this was remove the photo from the slideshow, so this removed the slide from the blog overview and single post, and kept the featured thumbnail.
This is a solution, but required extra steps and isn't intuitive to users. Will there or could there be an update or code modification to Coherence so that a single step to "set as featured image" will work?