I only heard someone transfering 80,000 bitcoins today, ready to sell, not the behavior of the exchange, it is a personal address, so be careful.
Guys like you who talk like this just for the purpose of trying to increase your post count sucks. Let us even assume what you are saying is for real, what proof do you have it is a personal address and not an exchange address, and what gives you the assurance that this person is ready to dump on the market except for the fact that you feel passing FUD is easier for your post count. At least, next time you want to share something like this, drop the proof if you ever want anyone to take you serious.
Market is Volatile, anything can happened at any given time at the market trading, Movement of 8k of Bitcoin is just a fraction of the volume of trading investment in Bitcoin, this does not affect in any way or what so ever on the price value of Bitcoin, there are a lot of indicators that contribute to the price movement, like, the issue on Scammer, Banned, Hacking, and the never ending issue on Regulation, not to mention the market trends, market structure, over all situation of the market.
Yes, the volatility of the market is what makes it easy for the response of bitcoin movement to cause panic easily with a quick dump which I am not surprised anyway since the news of the MtGox guy went flying around. It all balls down to FUD anyway and there is nothing at this stage we can do about it. The market is bound to have a huge correction and all these ones are just some quick driving factor to see it go lower and faster.