i'm just testing the new WP version.
I was looking for a plugin to crop images and just test your new release 0.71 with 3.5-RC2-22958
If i want to edit the post-thunbnail, the select field for All media items, Uploaded to this post disapear from the screen in the thickbox(Choose a Featured Image). If i disable your plugin, the select field is visible again. Maybe a bug?