lmighton on "YouTube embed"

I thought that I could do a YouTube embed within a wordpress.com blog. A brief forum search seems to confirm that. Yet when I paste the embed code into the HTML of my new post, it doesn't appear.
What am I doing wrong?

The code:

<object width="640" height="385"><param name="movie" value="http://www.youtube.com/v/VPX7AfbCVBY?fs=1&hl=en_US"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/VPX7AfbCVBY?fs=1&hl=en_US" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="640" height="385"></embed></object>