I "successfully" regenerated my thumbnails using the Regenerate Thumbnails Plugin as I added a variety of new image sizes to my site; however, I'm having difficulty getting these new images sizes to actual display. When I inspect each image it is still showing the old image size path in the src="". I don't have any cacheing plugins running (this is on a staging server.) Could this be an .htaccess issue?
Local: <img width="457" height="244" src="http://localhost:8888/example/wp-content/uploads/2012/10/ipad-mini-black1-457x244.jpg" class="attachment-large wp-post-image" alt="iPad mini" title="ipad-mini-black"> Staging: <img width="1200" height="640" src="http://example.com/staging/wp-content/uploads/2012/10/ipad-mini-black1.jpg" class="attachment-large wp-post-image" alt="iPad mini" title="ipad-mini-black">
As you can see, on my Local environment the image src is using the correct image sizes as at the end of the link it has the "456x244.jpg" crop, whereas on my Staging environment it is still using the original upload.