I'm using WordPress Multisite with a subdirectory configuration.
When calling calling feature image URLs with the following —
I get a returned URL of "/wp/wp-content/uploads/sites/8/2013/08/zerk2.jpg", but this image actually resides in "/wp/wp-content/uploads/2013/08/zerk2.jpg"
This blog is the default blog, so that would explain why its uploads aren't in the subdirectory for that blog.
The image displays correctly as a preview within the page's Edit screen.
Could this be because of the upload folder changes after 3.4?