We recently started having problems with embedding a video. I've seen numerous posts on media upload errors with 3.5, but we're on 3.5.1 which I assumed fixed all (or most) of those. Anyway, it's simple video embed code in a post:
<iframe width="560" height="315" src="http://www.youtube.com/embed/rbplYLmd0ts?list=UU1lUFFpXL5TXWzAFRS7MckA" frameborder="0" allowfullscreen></iframe>
Anybody have any idea what the problem is?