On my multi-author blog, some authors had been complaining that if they paste an embed code from YouTube in the post, it disappears upon saving the post.
Since I've never had this issue, I logged in as one of the authors (who has the problem) from the same computer I write my posts from. Sure enough, as soon as I pasted the YouTube code and saved the post, the embed tag disappeared.
I checked the author's profile and the "Visual Text Editor" box, was unchecked - which I ask all my authors to do.
Any idea WordPress gurus, what could be going wrong here? We are on WP 2.1