Some changes have occurred in the HTML 5 specification related to video and audio (the media portion of the spec). These are nicely outlined on the WHATWG blog.
After my blog post about cross domain restriction of audio and video there was a fairly lengthy discussion on the WHATWG mailing list about whether this should be done. The WHATWG blog entry mentioned previously goes into detail about this. The end result is that, for now, there will be no restriction. The W3C bug on the issue has been updated to reflect this.