In IE9, drag-and-dropping images from the desktop into the liveblog doesn't work -- it just loads the image in the browser, but doesn't upload it to the blog.
Same goes for the Chromium browser (this works in Google Chrome). This is because the browser doesn't support drag to upload abilities. Does IE9 allow you to upload anything else like that?
It turned out that IE9 just doesn't support drag and drop uploads.