I don’t see much edge for either bulls or bears tomorrow. From www.sentimentrader.com, statistically, triple witch OE is bullish 78% of the time since 1982. But the intraday model is very close to an overbought level which should give bears some credit tomorrow.
I have noticed a possible change in character as the rebound is so far very weak which is quite different from what we have used to be ever since the March. Giving the fact that the institution is putting more on distribution than accumulation (see: http://cobrasmarketview.blogspot.com/2009/06/06182009-institutional-buying-and.html), so better be careful of buying the dips.