George Buck, Chevron Brazil's chief, said the spill occurred as a result of an underestimate of pressure in the offshore oil reservoir, and an overestimate of the strength of the rock the company was drilling. Surface water oil sheen had been estimated at around 60 barrels a few days ago. The chatter on Main Street (a.k.a. Google, Yahoo! and other search sites) is always of interest to investors on Wall Street. Thus, each day, TheStreet compiles the stories that are trending on the Web, and highlights the news that could make stocks move.-- Written by Brittany Umar.