When someone posts a link on facebook, a script usually scans that link for any images, and displays a quick thumbnail next to the post. For certain URLs though (including m
Old question but recently I seemed to be running into same issue with thumbnail images from my link not showing in status updates on Facebook. I post for many clients and this is relatively new.
FB doesn't seem to like long URLs anymore — if you use a URL shortener such as goo.gl or bitly.com, the thumbnail from your link/post will appear in your FB update.