Story : The Speed Traders - Steve Kroft gets a rare look inside the secretive world of "high-frequency trading," a controversial technique the SEC is scrutinizing in which computers can make thousands of stock trades in less than a second. City of David - Lesley Stahl reports from under the city of Jerusalem from a controversial archeological dig that has become a flashpoint in the Israeli-Palestinian conflict. Lady Gaga - With her outrageous costumes and mega hit dance songs, Lady Gaga has become the world's most talked about entertainer.