What you failed to understand , that this sell off was created by Quant Hedgefunds and Institutions to sell everything after CISCOs numbers came in. They brutally organized into a selling mafia pounding so many shares and taking in profits. In just 4 sessions GOOG was down more than 100 points, BIDU down 120 points and AAPL down 42 points. Was there any good reason why these stocks were brutually sold off so rapidly? Therefore that created a technically an oversold condition and the real buyers stepped in after this manipulation game was exhausted and pushed the stocks to 319 points on solid volumes and momentum. There is lot more to come, dont under estimate the momentum of this rally and the fact its November/December when the markets respond bullishly. If I were you, I will get up early and cover my shorts.