I ended up fixing it by creating a new photo at the exact dimensions the featured photo is. So I'll just have to have 2 of each photo in my media library.

Since the bug was fixed, you shouldn't need to upload featured images that are the exact dimensions of your theme. The Columnist should be able to create the correctly sized thumbnails.

For the next featured image you set, could you try with a regularly-sized image to see if the issue is fixed for you? I only ask because if you were to continue uploading thumbnails sized exactly for The Columnist theme, and wanted to one day switch themes to a theme with larger thumbnails, you would need to reset all of your old featured images.

Thank you for your patience in helping us troubleshoot this.

I ended up fixing it by creating a new photo at the exact dimensions the featured photo is. So I'll just have to have 2 of each photo in my media library.

Seems like a redundant work around for a CMS that's supposed to be able to take care of that for you.

An update to WordPress.com caused some issues with images in different themes to be stretched, but has since been fixed.

It's likely that you're seeing a cached version of your site, having visited the site while the bug was present.

I would recommend clearing your browser cache to make sure that you hare viewing the most up-to-date version of your site.

For more information on Clearing Your Cache and Cookies:
http://en.support.wordpress.com/browser-issues/#clear-your-cache-and-cookies

Thanks.

In Safari they are compressed/stretched, while in other browsers they display fine.

Screenshot