I have delivered the change to the WordPress plugin repository in version 1.0.24. You can now tell SP to strip out the CDATA tags from the feed XML which ought to allow SP to inlude the media tags.
Note that when I tested your feed, I received a malformed XML error regarding one of your embed tag. Your embed tag parameters are not properly formed with the "" quotes around the parameter values.
Here is the error I received when trying to open your feed in firefox.
XML Parsing Error: not well-formed
Line Number 145, Column 14:<p><embed id=VideoPlayback src=http://video.google.co.uk/googleplayer.swf?docid=-9159164859238659487&hl=en&fs=true style=width:590px;height:468px allowFullScreen=true allowScriptAccess=always type=application/x-shockwave-flash> </embed></p>