Article Response - "A Very Bad Day For Markets"

I recently read an article on John Battelle's blog titled, "A Very Bad Day for Markets. What Does It Mean?". In the article, the author was confused about what "really" caused the significant decline in the market of 3% and denied that China was to blame. People commented on the article, saying that computer trading and derivative securities, along with illiquidity and overvaluation are to blame as well. Here is the link to the article - <http://battellemedia.com/archives/003406.php>