Looking at http://bitcoin.clarkmoody.com/widget/chart/ it appears (based on the red volume spikes) another huge sell off and Mt. Gox pulls the plug twice in a row. I believe they do not want to see BTC under $100 and think they can control it.
I was thinking about that too, DDOS never killed them before just made them slower. Today they're pulling out as soon as price is failing.