I wrote yesterday afternoon that things were getting overbought.  I also remarked

That said, with the market clearing the 200 day moving average (exponential) Friday, traders will be in a buy the dip mentality until a point comes when that level is again broken.  So as long as this S&P 500 holds the upper 1230s, I would not expect any rash pullbacks as buyers who missed this ferocious move now will be trying to jump in as performance anxiety hits.

In the opening moments today, we've finally seen the first material selling in three weeks.  And lo and behold, where did we bottom in the opening moments?  You can guess....

I would be surprised if this 200 day breaks with all the glee currently surrounding the market. So let's see if those dip buyers emerge later in the day.

EDIT 9:50 AM - Looks like the EU meeting for tomorrow has been pushed out to later in the week or early next week.... seems to be the main cause of the quick selloff.