Nothing showing up for me. Page source shows it's done something:
<code><object height='300' width='300'><param name='movie' value='http://www.mixcloud.com/media/swf/player/mixcloudLoader.swf?feed=www.mixcloud.com/artist/mix/'></param></object></code>
but the post shows up blank. The link works fine if copied and pasted into a browser, so it's generating the URL properly. Just won't display anything. Tried disabling all other plugins and re-installed both in WordPress and manually using FTP with the same result.
Let me know if you want more info.
Nice going getting a plugin written though, it's about time! Looking forward to getting it working.