San Diego Comic-Con 2010: Supernatural Panel: How Do You Top the End of the World? @ DreadCentral.com -- Cool photos of the panel at the bottom of the article.
Alice Jester's Comic Con Interview with Jensen Ackles -- Really great interview. :)
ecsmith34's SPN Panel Videos -- All 6 parts, the entire panel in good quality.
Gonturan74's SPN Panel Videos -- Even better quality videos of the entire panel, in 7 parts.
I'll add to this post w/more links if/when they become available.