"Algorithmic trading systems are only as smart as the guy who programmed them"
Watch this must see debate between Joe Saluzzi and Irene Aldridge on high frequency trading on CNBC (July 2009).
For more info on today's move read these posts at Kid Dynamite's Blog:
Part 1: Holy Cow. WTF STOCKS? Heres' What I'm Hearing
Part 2: More on the Crash - Possible Triggers, and High Frequency Trading